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TI-2026-55599 Aliases CVE-2026-80586GHSA-6f65-mfmh-h759

mptcp: options: reset DSS fields in case of unexpected size

Priority MEDIUM 49Published · 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: 16 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: mptcp: options: reset DSS fields in case of unexpected size A remote peer could send a malformed DSS with a wrong size, followed by another DSS or MPC + Data. In this case, the first suboption will be ignored, but leaving some fields written, which could lead to inconsistency or access uninitialized data. Explicitly reset the fields that could have been modified in case of unexpected size.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00399 34th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.266, 5.15.217, 6.1.184 +5Red Hat: 4 advisoriesRed Hat: 16 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
LinuxLinux5.6 and later5.10.266, 5.15.217, 6.1.184, 6.6.153, 6.12.105, 6.18.46, 7.1.10, 7.2Patch availableCNA
  • Linux VendorLinux Affected 5.6 and later Fixed in 5.10.266, 5.15.217, 6.1.184, 6.6.153, 6.12.105, 6.18.46, 7.1.10, 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 5.10.266, 5.15.217, 6.1.184, 6.6.153, 6.12.105, 6.18.46, 7.1.10, 7.2

Red Hat 4 advisories

  • RHSA-2026:93413 Released 2026-11-01 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • 10Base-SMTV kernel-modules-internal-6.12.0-211.72.1.el10_2
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.72.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.72.1.el10_2, kernel-64k-devel-6.12.0-211.72.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.72.1.el10_2, kernel-64k-6.12.0-211.72.1.el10_2, kernel-64k-core-6.12.0-211.72.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.72.1.el10_2, libperf-6.12.0-211.72.1.el10_2
    • Red Hat Enterprise Linux Hidden (v. 10) kernel-modules-internal-6.12.0-211.72.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.72.1.el10_2, kernel-rt-64k-6.12.0-211.72.1.el10_2, kernel-rt-64k-core-6.12.0-211.72.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.72.1.el10_2, kernel-rt-core-6.12.0-211.72.1.el10_2, kernel-rt-debug-6.12.0-211.72.1.el10_2 +9
  • RHSA-2026:93412 Released 2026-11-01 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.64.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.64.1.el9_8, kernel-64k-devel-5.14.0-687.64.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.64.1.el9_8, kernel-64k-5.14.0-687.64.1.el9_8, kernel-64k-core-5.14.0-687.64.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.64.1.el9_8, libperf-5.14.0-687.64.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.64.1.el9_8, kernel-rt-64k-5.14.0-687.64.1.el9_8, kernel-rt-64k-core-5.14.0-687.64.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.64.1.el9_8, kernel-rt-core-5.14.0-687.64.1.el9_8, kernel-rt-debug-5.14.0-687.64.1.el9_8 +9
  • RHSA-2026:89083 Released 2026-10-24 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.178.1.el8_10, kernel-4.18.0-553.178.1.el8_10, kernel-abi-stablelists-4.18.0-553.178.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.178.1.el8_10
Show 1 more Red Hat advisories
  • RHSA-2026:89082 Released 2026-10-24 · Red Hat rating Important
    kernel-rt security, bug fix, and enhancement update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.178.1.rt7.519.el8_10, kernel-rt-core-4.18.0-553.178.1.rt7.519.el8_10, kernel-rt-debug-4.18.0-553.178.1.rt7.519.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.178.1.rt7.519.el8_10, kernel-rt-core-4.18.0-553.178.1.rt7.519.el8_10, kernel-rt-debug-4.18.0-553.178.1.rt7.519.el8_10 +7

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 9AffectedNo fix yet
10Base-SMTVFixed RHSA-2026:93413
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:93413
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:93412
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:93413
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:89083
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:93412
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:89083
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:93413
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:93412
Red Hat Enterprise Linux Hidden (v. 10)Fixed RHSA-2026:93413
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:89082
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:89082
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:93413
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:93412
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:93413
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:93412
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-80586
  2. 2026-10-03 Alias added: GHSA-6f65-mfmh-h759
  3. 2026-10-18 CISA SSVC decision points changed
  4. 2026-10-26 Fix available: RHSA-2026:89083 · Red Hat
  5. 2026-10-26 Fix available: Red Hat Enterprise Linux BaseOS (v. 8), Red Hat Enterprise Linux CRB (v. 8) · Red Hat
  6. 2026-10-26 Fix available: RHSA-2026:89082 · Red Hat
  7. 2026-10-26 Fix available: Red Hat Enterprise Linux NFV (v. 8), Red Hat Enterprise Linux RT (v. 8) · Red Hat
  8. 2026-11-02 Fix available: RHSA-2026:93413 · Red Hat
  9. 2026-11-02 Fix available: RHSA-2026:93412 · Red Hat
  10. 2026-11-02 Fix available: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux AppStream (v. 9) +9 · Red Hat

References

Other 8

  • 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