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TI-2025-26618 Aliases CVE-2025-39946GHSA-cgf5-f6fj-4v5q

tls: make sure to abort the stream if headers are bogus

Priority MEDIUM 61Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 5 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: tls: make sure to abort the stream if headers are bogus Normally we wait for the socket to buffer up the whole record before we service it. If the socket has a tiny buffer, however, we read out the data sooner, to prevent connection stalls. Make sure that we abort the connection when we find out late that the record is actually invalid. Retrying the parsing is fine in itself but since we copy some more data each time before we parse we can overflow the allocated skb space. Constructing a scenario in which we're under pressure without enough data in the socket to parse the length upfront is quite hard. syzbot figured out a way to do this by serving us the header in small OOB sends, and then filling in the recvbuf with a large normal send. Make sure that tls_rx_msg_size() aborts strp, if we reach an invalid record there's really no way to recover.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.10258 95th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.154, 6.6.108, 6.12.49 +2Red Hat: 1 advisoryRed Hat: 5 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.0 and later6.1.154, 6.6.108, 6.12.49, 6.16.9, 6.17Patch availableCNA
  • Linux VendorLinux Affected 6.0 and later Fixed in 6.1.154, 6.6.108, 6.12.49, 6.16.9, 6.17 Patch available CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.0 to before 6.1.154; 6.2 to before 6.6.108; 6.7 to before 6.12.49; 6.13 to before 6.16.9VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*6.17 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*6.17 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*6.17 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*6.17 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:*6.17 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:*6.17 rc6VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.0 to before 6.1.154; 6.2 to before 6.6.108; 6.7 to before 6.12.49; 6.13 to before 6.16.9 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:* Versions 6.17 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:* Versions 6.17 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:* Versions 6.17 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:* Versions 6.17 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:* Versions 6.17 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:* Versions 6.17 rc6 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.154, 6.6.108, 6.12.49, 6.16.9, 6.17

Red Hat 1 advisory

  • RHSA-2025:21463 Released 2025-11-17 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-124.11.1.el10_1, kernel-64k-debug-devel-matched-6.12.0-124.11.1.el10_1, kernel-64k-devel-6.12.0-124.11.1.el10_1 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-124.11.1.el10_1, kernel-64k-6.12.0-124.11.1.el10_1, kernel-64k-core-6.12.0-124.11.1.el10_1 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-124.11.1.el10_1, libperf-6.12.0-124.11.1.el10_1
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-124.11.1.el10_1, kernel-rt-64k-6.12.0-124.11.1.el10_1, kernel-rt-64k-core-6.12.0-124.11.1.el10_1 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-124.11.1.el10_1, kernel-rt-core-6.12.0-124.11.1.el10_1, kernel-rt-debug-6.12.0-124.11.1.el10_1 +9

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:21463
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2025:21463
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2025:21463
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2025:21463
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2025:21463
Not affected: 3 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-39946
  2. 2026-10-03 Alias added: GHSA-cgf5-f6fj-4v5q

References

Patch 5

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences