CVE-2026-64037
published 2026-07-19CVE-2026-64037: In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled When the TLC…
PriorityP350critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.43%
35.5th percentile
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled
When the TLC notification disables AMSDU for a TID, the MLD driver sets
max_tid_amsdu_len to the sentinel value 1. The TSO segmentation path in
iwl_mld_tx_tso_segment() checks for zero but not for this sentinel,
allowing it to reach the num_subframes calculation:
num_subframes = (max_tid_amsdu_len + pad) / (subf_len + pad)
= (1 + 2) / (1534 + 2) = 0
This zero propagates to iwl_tx_tso_segment() which sets:
gso_size = num_subframes * mss = 0
Calling skb_gso_segment() with gso_size=0 creates over 32000 tiny
segments from a single GSO skb. This floods the TX ring with ~1024
micro-frames (the rest are purged), creating a massive burst of TX
completion events that can lead to memory corruption and a subsequent
use-after-free in TCP's retransmit queue (refcount underflow in
tcp_shifted_skb, NULL deref in tcp_rack_detect_loss).
The MVM driver is immune because it checks mvmsta->amsdu_enabled before
reaching the num_subframes calculation. The MLD driver has no equivalent
bitmap check and relies solely on max_tid_amsdu_len, which does not
catch the sentinel value.
Fix this by detecting the sentinel value (max_tid_amsdu_len == 1) at the
existing check and falling back to non-AMSDU TSO segmentation. Also add
a WARN_ON_ONCE guard after the num_subframes division as defense-in-depth
to catch any future code paths that produce zero through a different
mechanism.
Affected
23 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= d1e879ec600f9b3bdd253167533959facfefb17b < 9e360e610a73f62432e986775023d5382773f045 | 9e360e610a73f62432e986775023d5382773f045 |
| linux | linux | >= d1e879ec600f9b3bdd253167533959facfefb17b < cbe1c8245e4469d1aa6e12e5d913611376d23788 | cbe1c8245e4469d1aa6e12e5d913611376d23788 |
| linux | linux | >= d1e879ec600f9b3bdd253167533959facfefb17b < 92cee08dc4f00e77fd1317e4343c5d458b0abab7 | 92cee08dc4f00e77fd1317e4343c5d458b0abab7 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 6.15 < 6.18.34 | 6.18.34 |
| linux | linux_kernel | >= 6.19 < 7.0.11 | 7.0.11 |
| ubuntu | linux-aws | — | — |
| ubuntu | linux-azure | — | — |
| ubuntu | linux-azure-7.0 | — | — |
| ubuntu | linux-azure-fde | — | — |
| ubuntu | linux-gcp-7.0 | — | — |
| ubuntu | linux-ibm | — | — |
| ubuntu | linux-nvidia | — | — |
| ubuntu | linux-nvidia-7.0 | — | — |
| ubuntu | linux-nvidia-bos | — | — |
| ubuntu | linux-oracle | — | — |
| ubuntu | linux-oracle-7.0 | — | — |
| ubuntu | linux-raspi | — | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat9.8CRITICAL
vendor_ubuntu9.1CRITICAL
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Ubuntu
Linux kernel (Oracle) vulnerabilities
vendor_ubuntu·2026-09-29·CVSS 9.1
CVE-2026-64191 [CRITICAL] Linux kernel (Oracle) vulnerabilities
Title: Linux kernel (Oracle) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were d
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-09-22·CVSS 9.1
CVE-2026-52938 [CRITICAL] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were di
Ubuntu
Linux kernel (GCP) vulnerabilities
vendor_ubuntu·2026-09-07·CVSS 9.1
CVE-2026-52938 [CRITICAL] Linux kernel (GCP) vulnerabilities
Title: Linux kernel (GCP) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were disc
Ubuntu
Linux kernel (NVIDIA) vulnerabilities
vendor_ubuntu·2026-08-20·CVSS 7.0
CVE-2026-64234 [HIGH] Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
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:
- x86 platform drivers;
- Cryptographic API;
- PSP security protocol;
- ARM32 architecture;
- ARM64 architecture;
- MIPS architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- User-Mode Linux (UML);
- x
Ubuntu
Linux kernel (NVIDIA BaseOS) vulnerabilities
vendor_ubuntu·2026-08-20·CVSS 7.0
CVE-2026-64109 [HIGH] Linux kernel (NVIDIA BaseOS) vulnerabilities
Title: Linux kernel (NVIDIA BaseOS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
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:
- x86 platform drivers;
- Cryptographic API;
- PSP security protocol;
- ARM32 architecture;
- ARM64 architecture;
- MIPS architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- User-Mode Linux (UM
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-07-28·CVSS 7.0
CVE-2026-64231 [HIGH] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
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:
- x86 platform drivers;
- Cryptographic API;
- PSP security protocol;
- ARM32 architecture;
- ARM64 architecture;
- MIPS architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- User-Mode Linux (UML);
- x86 archit
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-07-24·CVSS 2.0
CVE-2026-64107 [LOW] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
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:
- x86 platfor
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-07-23·CVSS 7.0
CVE-2026-64107 [HIGH] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
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:
- x86 platform drivers;
- PSP security protocol;
- ARM32 architecture;
- ARM64 architecture;
- MIPS architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer
Red Hat
kernel: wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled
vendor_redhat·2026-07-19·CVSS 9.8
CVE-2026-64037 [CRITICAL] CWE-476 kernel: wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled
kernel: wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled
When the TLC notification disables AMSDU for a TID, the MLD driver sets
max_tid_amsdu_len to the sentinel value 1. The TSO segmentation path in
iwl_mld_tx_tso_segment() checks for zero but not for this sentinel,
allowing it to reach the num_subframes calculation:
num_subframes = (max_tid_amsdu_len + pad) / (subf_len + pad)
= (1 + 2) / (1534 + 2) = 0
This zero propagates to iwl_tx_tso_segment() which sets:
gso_size = num_subframes * mss = 0
Calling skb_gso_segment() with gso_size=0 creates over 32000 tiny
segments from a single GSO skb. This floods the TX ring with ~102
VulDB
Linux Kernel up to 6.18.33/7.0.10 MLD driver iwl_mld_tx_tso_segment max_tid_amsdu_len use after free (Nessus ID 344851)
vuldb·2026-09-12·CVSS 9.8
CVE-2026-64037 [CRITICAL] Linux Kernel up to 6.18.33/7.0.10 MLD driver iwl_mld_tx_tso_segment max_tid_amsdu_len use after free (Nessus ID 344851)
A vulnerability classified as very critical was found in Linux Kernel up to 6.18.33/7.0.10. Impacted is the function iwl_mld_tx_tso_segment of the component MLD driver. Such manipulation of the argument max_tid_amsdu_len leads to use after free.
This vulnerability is listed as CVE-2026-64037. The attack may be performed from remote. There is no available exploit.
Upgrading the affected component is advised.
GHSA
In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled When the TLC notification disables AMSDU for a TID, the
ghsa_unreviewed·2026-07-19
CVE-2026-64037 [CRITICAL] In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled When the TLC notification disables AMSDU for a TID, the
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled
When the TLC notification disables AMSDU for a TID, the MLD driver sets
max_tid_amsdu_len to the sentinel value 1. The TSO segmentation path in
iwl_mld_tx_tso_segment() checks for zero but not for this sentinel,
allowing it to reach the num_subframes calculation:
num_subframes = (max_tid_amsdu_len + pad) / (subf_len + pad)
= (1 + 2) / (1534 + 2) = 0
This zero propagates to iwl_tx_tso_segment() which sets:
gso_size = num_subframes * mss = 0
Calling skb_gso_segment() with gso_size=0 creates over 32000 tiny
segments from a single GSO skb. This floods the TX ring with ~1024
micro-frames (the rest are purged), creating a massive burst of TX
completi
No detection rules found.
No public exploits indexed.
2026-07-19
Published