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TI-2026-55650 Aliases CVE-2026-80637GHSA-h35g-h9xw-jfv9

netfilter: synproxy: fix unaligned memory access in timestamp adjustment

Priority MEDIUM 40Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 4 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: netfilter: synproxy: fix unaligned memory access in timestamp adjustment Use get_unaligned_be32() and put_unaligned_be32() to safely read and write the timestamp fields. This prevents performance degradation due to unaligned memory access or even a crash on strict alignment architectures. This follows the implementation of timestamp parsing in the networking stack at tcp_parse_options() and synproxy_parse_options().

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00585 48th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.191, 6.6.160, 6.12.97 +3Red Hat: 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux3.12 and later6.1.191, 6.6.160, 6.12.97, 6.18.40, 7.1.5, 7.2Patch availableCNA
  • Linux VendorLinux Affected 3.12 and later Fixed in 6.1.191, 6.6.160, 6.12.97, 6.18.40, 7.1.5, 7.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.160, 6.12.97, 6.18.40, 7.1.5, 7.2

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-80637
  2. 2026-10-03 Alias added: GHSA-h35g-h9xw-jfv9
  3. 2026-10-18 CISA SSVC decision points changed
  4. 2026-10-18 Priority changed: LOW → MEDIUM
  5. 2026-10-21 Fix available: Linux/[email protected], Linux/Linux@95cda0446f51077c343fdd8264be2737eb25a6c3 · CNA
  6. 2026-10-21 1 new reference · CNA
  7. 2026-10-28 EPSS moved to the 50th–90th percentile
  8. 2026-10-30 Fix available: Linux/[email protected], Linux/Linux@b30a2d56ee47282f6a46cb2f50e315b2414851fe · CNA
  9. 2026-10-30 1 new reference · CNA
  10. 2026-11-07 EPSS moved to the below the 50th percentile

References

Other 6

  • 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-2021-02452 Incorrect authorization in Ubuntu linux kernel 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
See all 21741 →

Sources

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