CVE-2024-49940
published 2024-10-21CVE-2024-49940: In the Linux kernel, the following vulnerability has been resolved: l2tp: prevent possible tunnel refcount underflow When a session is created, it sets a…
PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.22%
12.8th percentile
In the Linux kernel, the following vulnerability has been resolved:
l2tp: prevent possible tunnel refcount underflow
When a session is created, it sets a backpointer to its tunnel. When
the session refcount drops to 0, l2tp_session_free drops the tunnel
refcount if session->tunnel is non-NULL. However, session->tunnel is
set in l2tp_session_create, before the tunnel refcount is incremented
by l2tp_session_register, which leaves a small window where
session->tunnel is non-NULL when the tunnel refcount hasn't been
bumped.
Moving the assignment to l2tp_session_register is trivial but
l2tp_session_create calls l2tp_session_set_header_len which uses
session->tunnel to get the tunnel's encap. Add an encap arg to
l2tp_session_set_header_len to avoid using session->tunnel.
If l2tpv3 sessions have colliding IDs, it is possible for
l2tp_v3_session_get to race with l2tp_session_register and fetch a
session which doesn't yet have session->tunnel set. Add a check for
this case.
Affected
31 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.11.4-1 (forky) | linux 6.11.4-1 (forky) |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | >= 3.16.54 < 3.17 | 3.17 |
| linux | linux | >= 3.2.99 < 3.3 | 3.3 |
| linux | linux | >= 3953ae7b218df4d1e544b98a393666f9ae58a78c < f7415e60c25a6108cd7955a20b2e66b6251ffe02 | f7415e60c25a6108cd7955a20b2e66b6251ffe02 |
| linux | linux | >= 3953ae7b218df4d1e544b98a393666f9ae58a78c < 24256415d18695b46da06c93135f5b51c548b950 | 24256415d18695b46da06c93135f5b51c548b950 |
| linux | linux | >= 4.14.182 < 4.15 | 4.15 |
| linux | linux | >= 4.4.225 < 4.5 | 4.5 |
| linux | linux | >= 4.9.225 < 4.10 | 4.10 |
| linux | linux_kernel | < 6.11.3 | 6.11.3 |
| linux | linux_kernel | >= 0 < 6.11.4-1 | 6.11.4-1 |
| linux | linux_kernel | >= 0 < 6.11.4-1 | 6.11.4-1 |
| linux | linux_kernel | >= 0 < 6.11.0-18.18 | 6.11.0-18.18 |
| msrc | azl3_kernel_6.6.104.2-4_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.112.1-2_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.117.1-1_on_azure_linux_3.0 | — | — |
| 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 | — | — |
| msrc | azl3_kernel_6.6.121.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.126.1-1_on_azure_linux_3.0 | — | — |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2025-02-28
CVE-2024-47738 Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Attila Szász discovered that the HFS+ file system implementation in the
Linux Kernel contained a heap overflow vulnerability. An attacker could use
a specially crafted file system image that, when mounted, could cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2025-0927)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- SuperH RISC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
-
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2025-02-19
CVE-2024-47738 Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- SuperH RISC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
- Drivers core;
- ATA over ethernet (AOE) driver;
- RAM backed block device driver;
- Network block device driver;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bluetooth drivers;
- TPM device driver;
- Clock fr
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2025-02-19
CVE-2024-49996 Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Attila Szász discovered that the HFS+ file system implementation in the
Linux Kernel contained a heap overflow vulnerability. An attacker could use
a specially crafted file system image that, when mounted, could cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2025-0927)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- SuperH RISC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
-
Red Hat
kernel: l2tp: prevent possible tunnel refcount underflow
vendor_redhat·2024-10-21·CVSS 5.5
CVE-2024-49940 [MEDIUM] CWE-672 kernel: l2tp: prevent possible tunnel refcount underflow
kernel: l2tp: prevent possible tunnel refcount underflow
In the Linux kernel, the following vulnerability has been resolved:
l2tp: prevent possible tunnel refcount underflow
When a session is created, it sets a backpointer to its tunnel. When
the session refcount drops to 0, l2tp_session_free drops the tunnel
refcount if session->tunnel is non-NULL. However, session->tunnel is
set in l2tp_session_create, before the tunnel refcount is incremented
by l2tp_session_register, which leaves a small window where
session->tunnel is non-NULL when the tunnel refcount hasn't been
bumped.
Moving the assignment to l2tp_session_register is trivial but
l2tp_session_create calls l2tp_session_set_header_len which uses
session->tunnel to get the tunnel's encap. Add an encap arg to
l2tp_session_set_header_le
Microsoft
l2tp: prevent possible tunnel refcount underflow
vendor_msrc·2024-10-08·CVSS 5.5
CVE-2024-49940 [MEDIUM] l2tp: prevent possible tunnel refcount underflow
l2tp: prevent possible tunnel refcount underflow
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
Linux: Linux
Customer Action Required: Yes
Debian
CVE-2024-49940: linux - In the Linux kernel, the following vulnerability has been resolved: l2tp: preve...
vendor_debian·2024·CVSS 5.5
CVE-2024-49940 [MEDIUM] CVE-2024-49940: linux - In the Linux kernel, the following vulnerability has been resolved: l2tp: preve...
In the Linux kernel, the following vulnerability has been resolved: l2tp: prevent possible tunnel refcount underflow When a session is created, it sets a backpointer to its tunnel. When the session refcount drops to 0, l2tp_session_free drops the tunnel refcount if session->tunnel is non-NULL. However, session->tunnel is set in l2tp_session_create, before the tunnel refcount is incremented by l2tp_session_register, which leaves a small window where session->tunnel is non-NULL when the tunnel refcount hasn't been bumped. Moving the assignment to l2tp_session_register is trivial but l2tp_session_create calls l2tp_session_set_header_len which uses session->tunnel to get the tunnel's encap. Add an encap arg to l2tp_session_set_header_len to avoid using session->tunnel. If l2tpv3 sessions have
OSV
linux-oem-6.11 vulnerabilities
osv·2025-02-28
CVE-2025-0927 linux-oem-6.11 vulnerabilities
linux-oem-6.11 vulnerabilities
Attila Szász discovered that the HFS+ file system implementation in the
Linux Kernel contained a heap overflow vulnerability. An attacker could use
a specially crafted file system image that, when mounted, could cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2025-0927)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- SuperH RISC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
-
OSV
linux-aws, linux-azure, linux-gcp, linux-oracle, linux-raspi, linux-realtime vulnerabilities
osv·2025-02-19
linux-aws, linux-azure, linux-gcp, linux-oracle, linux-raspi, linux-realtime vulnerabilities
linux-aws, linux-azure, linux-gcp, linux-oracle, linux-raspi, linux-realtime vulnerabilities
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- SuperH RISC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI drivers;
- Drivers core;
- ATA over ethernet (AOE) driver;
- RAM backed block device driver;
- Network block device driver;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bluetooth drivers;
- TPM device driver;
- Clock framework a
OSV
linux, linux-lowlatency vulnerabilities
osv·2025-02-19
CVE-2025-0927 linux, linux-lowlatency vulnerabilities
linux, linux-lowlatency vulnerabilities
Attila Szász discovered that the HFS+ file system implementation in the
Linux Kernel contained a heap overflow vulnerability. An attacker could use
a specially crafted file system image that, when mounted, could cause a
denial of service (system crash) or possibly execute arbitrary code.
(CVE-2025-0927)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- SuperH RISC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- ACPI d
OSV
CVE-2024-49940: In the Linux kernel, the following vulnerability has been resolved: l2tp: prevent possible tunnel refcount underflow When a session is created, it set
osv·2024-10-21·CVSS 5.5
CVE-2024-49940 [MEDIUM] CVE-2024-49940: In the Linux kernel, the following vulnerability has been resolved: l2tp: prevent possible tunnel refcount underflow When a session is created, it set
In the Linux kernel, the following vulnerability has been resolved: l2tp: prevent possible tunnel refcount underflow When a session is created, it sets a backpointer to its tunnel. When the session refcount drops to 0, l2tp_session_free drops the tunnel refcount if session->tunnel is non-NULL. However, session->tunnel is set in l2tp_session_create, before the tunnel refcount is incremented by l2tp_session_register, which leaves a small window where session->tunnel is non-NULL when the tunnel refcount hasn't been bumped. Moving the assignment to l2tp_session_register is trivial but l2tp_session_create calls l2tp_session_set_header_len which uses session->tunnel to get the tunnel's encap. Add an encap arg to l2tp_session_set_header_len to avoid using session->tunnel. If l2tpv3 sessions have
GHSA
GHSA-h9jc-p2cr-c4rx: In the Linux kernel, the following vulnerability has been resolved:
l2tp: prevent possible tunnel refcount underflow
When a session is created, it s
ghsa_unreviewed·2024-10-21
CVE-2024-49940 [MEDIUM] GHSA-h9jc-p2cr-c4rx: In the Linux kernel, the following vulnerability has been resolved:
l2tp: prevent possible tunnel refcount underflow
When a session is created, it s
In the Linux kernel, the following vulnerability has been resolved:
l2tp: prevent possible tunnel refcount underflow
When a session is created, it sets a backpointer to its tunnel. When
the session refcount drops to 0, l2tp_session_free drops the tunnel
refcount if session->tunnel is non-NULL. However, session->tunnel is
set in l2tp_session_create, before the tunnel refcount is incremented
by l2tp_session_register, which leaves a small window where
session->tunnel is non-NULL when the tunnel refcount hasn't been
bumped.
Moving the assignment to l2tp_session_register is trivial but
l2tp_session_create calls l2tp_session_set_header_len which uses
session->tunnel to get the tunnel's encap. Add an encap arg to
l2tp_session_set_header_len to avoid using session->tunnel.
If l2tpv3 sessions h
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2024-10-21
Published