CVE-2025-68291
published 2025-12-16CVE-2025-68291: In the Linux kernel, the following vulnerability has been resolved: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose()…
PriorityP423medium6.4
EPSS
0.19%
9.0th percentile
In the Linux kernel, the following vulnerability has been resolved:
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
syzbot reported divide-by-zero in __tcp_select_window() by
MPTCP socket. [0]
We had a similar issue for the bare TCP and fixed in commit
499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead
of 0").
Let's apply the same fix to mptcp_do_fastclose().
[0]:
Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336
Code: ff ff ff 44 89 f1 d3 e0 89 c1 f7 d1 41 01 cc 41 21 c4 e9 a9 00 00 00 e8 ca 49 01 f8 e9 9c 00 00 00 e8 c0 49 01 f8 44 89 e0 99 7c 24 1c 41 29 d4 48 bb 00 00 00 00 00 fc ff df e9 80 00 00 00
RSP: 0018:ffffc90003017640 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88807b469e40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003017730 R08: ffff888033268143 R09: 1ffff1100664d028
R10: dffffc0000000000 R11: ffffed100664d029 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 000055557faa0500(0000) GS:ffff888126135000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f64a1912ff8 CR3: 0000000072122000 CR4: 00000000003526f0
Call Trace:
tcp_select_window net/ipv4/tcp_output.c:281 [inline]
__tcp_transmit_skb+0xbc7/0x3aa0 net/ipv4/tcp_output.c:1568
tcp_transmit_skb net/ipv4/tcp_output.c:1649 [inline]
tcp_send_active_reset+0x2d1/0x5b0 net/ipv4/tcp_output.c:3836
mptcp_do_fastclose+0x27e/0x380 net/mptcp/protocol.c:2793
mptcp_disconnect+0x238/0x710 net/mptcp/protocol.c:3253
mptcp_sendmsg_fastopen+0x2f8/0x580 net/mptcp/protocol.c:1776
mptcp_sendmsg+0x1774/0x1980 net/mptcp/protocol.c:1855
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0xe5/0x
Affected
38 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.162-1 (bookworm) | linux 6.1.162-1 (bookworm) |
| debian | linux-6.1 | < linux 6.1.162-1 (bookworm) | linux 6.1.162-1 (bookworm) |
| linux | linux | >= 3a13454fd098ed51e733958488f8ec62859a9ed8 < eee39f83246a81d970a9ecb7392b7ab74e660094 | eee39f83246a81d970a9ecb7392b7ab74e660094 |
| linux | linux | >= 6.1.159 < 6.1.160 | 6.1.160 |
| linux | linux | >= 6.12.60 < 6.12.61 | 6.12.61 |
| linux | linux | >= 6.17.10 < 6.17.11 | 6.17.11 |
| linux | linux | >= 6.6.119 < 6.6.120 | 6.6.120 |
| linux | linux | >= 9ea05fabce31ff93a0adae8221c58bc6d7b832f3 < 46b8b58f93f1b383c3840fc6e8fab6c3bce9295f | 46b8b58f93f1b383c3840fc6e8fab6c3bce9295f |
| linux | linux | >= ae155060247be8dcae3802a95bd1bdf93ab3215d < f07f4ea53e22429c84b20832fa098b5ecc0d4e35 | f07f4ea53e22429c84b20832fa098b5ecc0d4e35 |
| linux | linux | >= c4f7b0916b95fd2226e5ab98882482b08f52e1c0 < 88163f85d59b4164884df900ee171720fd26686b | 88163f85d59b4164884df900ee171720fd26686b |
| linux | linux | >= f6fb2cbc91a81178dea23d463503b4525a76825d < 05f5e26d488cdc7abc2a826cf1071782d5a21203 | 05f5e26d488cdc7abc2a826cf1071782d5a21203 |
| linux | linux_kernel | >= 0 < 6.1.162-1 | 6.1.162-1 |
| linux | linux_kernel | >= 0 < 6.17.11-1 | 6.17.11-1 |
| linux | linux_kernel | >= 6.1.159 < 6.1.160 | 6.1.160 |
| linux | linux_kernel | >= 6.12.60 < 6.12.61 | 6.12.61 |
| linux | linux_kernel | >= 6.17.10 < 6.17.11 | 6.17.11 |
| linux | linux_kernel | >= 6.6.119 < 6.6.120 | 6.6.120 |
| msrc | azl3_kernel_6.6.119.3-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.119.3-3_on_azure_linux_3.0 | — | — |
| ubuntu | linux-aws-fips | — | — |
| ubuntu | linux-azure | — | — |
| ubuntu | linux-azure-6.8 | — | — |
| ubuntu | linux-azure-fips | — | — |
| ubuntu | linux-fips | — | — |
| ubuntu | linux-gcp-6.8 | — | — |
CVSS provenance
vendor_ubuntu6.4MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5HIGH
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Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-06-16·CVSS 6.4
CVE-2026-23262 [MEDIUM] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality. (CVE-2024-36347)
It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
It was discovered that the Linux kernel did not properly handle share
Ubuntu
Linux kernel (NVIDIA Tegra) vulnerabilities
vendor_ubuntu·2026-05-11·CVSS 6.4
CVE-2025-68344 [MEDIUM] Linux kernel (NVIDIA Tegra) vulnerabilities
Title: Linux kernel (NVIDIA Tegra) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality. (CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network b
Ubuntu
Linux kernel (GCP) vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-68344 [MEDIUM] Linux kernel (GCP) vulnerabilities
Title: Linux kernel (GCP) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network block devi
Ubuntu
Linux kernel (Azure FIPS) vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-68756 [MEDIUM] Linux kernel (Azure FIPS) vulnerabilities
Title: Linux kernel (Azure FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality. (CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network blo
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-68756 [MEDIUM] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality. (CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network block de
Ubuntu
Linux kernel (Low Latency NVIDIA) vulnerabilities
vendor_ubuntu·2026-04-28·CVSS 6.4
CVE-2025-68256 [MEDIUM] Linux kernel (Low Latency NVIDIA) vulnerabilities
Title: Linux kernel (Low Latency NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Net
Ubuntu
Linux kernel (Oracle) vulnerabilities
vendor_ubuntu·2026-04-23·CVSS 6.4
CVE-2025-68801 [MEDIUM] Linux kernel (Oracle) vulnerabilities
Title: Linux kernel (Oracle) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network block d
Ubuntu
Linux kernel (Raspberry Pi Real-time) vulnerabilities
vendor_ubuntu·2026-04-23·CVSS 6.4
CVE-2025-71069 [MEDIUM] Linux kernel (Raspberry Pi Real-time) vulnerabilities
Title: Linux kernel (Raspberry Pi Real-time) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
-
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-04-23·CVSS 6.4
CVE-2025-68801 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network block device dri
Ubuntu
Linux kernel (FIPS) vulnerabilities
vendor_ubuntu·2026-04-17·CVSS 6.4
CVE-2025-68788 [MEDIUM] Linux kernel (FIPS) vulnerabilities
Title: Linux kernel (FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network block dev
Ubuntu
Linux kernel (Real-time) vulnerabilities
vendor_ubuntu·2026-04-17·CVSS 6.4
CVE-2025-71132 [MEDIUM] Linux kernel (Real-time) vulnerabilities
Title: Linux kernel (Real-time) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network bloc
Ubuntu
Linux kernel (NVIDIA) vulnerabilities
vendor_ubuntu·2026-04-17·CVSS 6.4
CVE-2025-68788 [MEDIUM] Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network block d
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-04-16·CVSS 6.4
CVE-2025-71132 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- MIPS architecture;
- PowerPC architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
- Network block device dri
Red Hat
kernel: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose()
vendor_redhat·2025-12-16·CVSS 5.5
CVE-2025-68291 [HIGH] CWE-909 kernel: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose()
kernel: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose()
In the Linux kernel, the following vulnerability has been resolved:
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
syzbot reported divide-by-zero in __tcp_select_window() by
MPTCP socket. [0]
We had a similar issue for the bare TCP and fixed in commit
499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead
of 0").
Let's apply the same fix to mptcp_do_fastclose().
[0]:
Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336
Microsoft
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
vendor_msrc·2025-12-09·CVSS 5.5
CVE-2025-68291 [MEDIUM] mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
Mariner: Mariner
Linux: Linux
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade
Debian
CVE-2025-68291: linux - In the Linux kernel, the following vulnerability has been resolved: mptcp: Init...
vendor_debian·2025
CVE-2025-68291 CVE-2025-68291: linux - In the Linux kernel, the following vulnerability has been resolved: mptcp: Init...
In the Linux kernel, the following vulnerability has been resolved: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose(). syzbot reported divide-by-zero in __tcp_select_window() by MPTCP socket. [0] We had a similar issue for the bare TCP and fixed in commit 499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead of 0"). Let's apply the same fix to mptcp_do_fastclose(). [0]: Oops: divide error: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336 Code: ff ff ff 44 89 f1 d3 e0 89 c1 f7 d1 41 01 cc 41 21 c4 e9 a9 00 00 00 e8 ca 49 01 f8 e9 9c 00
OSV
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
osv·2025-12-16
CVE-2025-68291 mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
In the Linux kernel, the following vulnerability has been resolved:
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
syzbot reported divide-by-zero in __tcp_select_window() by
MPTCP socket. [0]
We had a similar issue for the bare TCP and fixed in commit
499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead
of 0").
Let's apply the same fix to mptcp_do_fastclose().
[0]:
Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336
Co
OSV
CVE-2025-68291: In the Linux kernel, the following vulnerability has been resolved: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastc
osv·2025-12-16
CVE-2025-68291 CVE-2025-68291: In the Linux kernel, the following vulnerability has been resolved: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastc
In the Linux kernel, the following vulnerability has been resolved: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose(). syzbot reported divide-by-zero in __tcp_select_window() by MPTCP socket. [0] We had a similar issue for the bare TCP and fixed in commit 499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead of 0"). Let's apply the same fix to mptcp_do_fastclose(). [0]: Oops: divide error: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336 Code: ff ff ff 44 89 f1 d3 e0 89 c1 f7 d1 41 01 cc 41 21 c4 e9 a9 00 00 00 e8 ca 49 01 f8 e9 9c 00
GHSA
GHSA-92x9-c26m-74g2: In the Linux kernel, the following vulnerability has been resolved:
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fast
ghsa_unreviewed·2025-12-16
CVE-2025-68291 GHSA-92x9-c26m-74g2: In the Linux kernel, the following vulnerability has been resolved:
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fast
In the Linux kernel, the following vulnerability has been resolved:
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
syzbot reported divide-by-zero in __tcp_select_window() by
MPTCP socket. [0]
We had a similar issue for the bare TCP and fixed in commit
499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead
of 0").
Let's apply the same fix to mptcp_do_fastclose().
[0]:
Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336
Code: ff ff ff 44 89 f1 d3 e0 89 c1 f7 d1 41 01 cc 41 21 c4 e9 a9 00 00 00 e8 ca 49 01 f8 e9
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2025-68291 kernel: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose()
bugzilla·2025-12-16
CVE-2025-68291 [HIGH] CVE-2025-68291 kernel: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose()
CVE-2025-68291 kernel: mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose()
In the Linux kernel, the following vulnerability has been resolved:
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
syzbot reported divide-by-zero in __tcp_select_window() by
MPTCP socket. [0]
We had a similar issue for the bare TCP and fixed in commit
499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead
of 0").
Let's apply the same fix to mptcp_do_fastclose().
[0]:
Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv
Wiz
CVE-2025-68291 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz
CVE-2025-68291 CVE-2025-68291 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2025-68291 :
Linux Kernel vulnerability analysis and mitigation
In the Linux kernel, the following vulnerability has been resolved:
mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().
syzbot reported divide-by-zero in __tcp_select_window() by
MPTCP socket. [0]
We had a similar issue for the bare TCP and fixed in commit
499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead
of 0").
Let's apply the same fix to mptcp_do_fastclose().
[0]:
Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336
Code: ff ff ff 44 89
https://git.kernel.org/stable/c/05f5e26d488cdc7abc2a826cf1071782d5a21203https://git.kernel.org/stable/c/46b8b58f93f1b383c3840fc6e8fab6c3bce9295fhttps://git.kernel.org/stable/c/88163f85d59b4164884df900ee171720fd26686bhttps://git.kernel.org/stable/c/eee39f83246a81d970a9ecb7392b7ab74e660094https://git.kernel.org/stable/c/f07f4ea53e22429c84b20832fa098b5ecc0d4e35https://cert-portal.siemens.com/productcert/html/ssa-019113.html
2025-12-16
Published