CVE-2026-68123
openvswitch: fix GSO userspace truncation underflow
CRITICAL 9.8
At a glance
- Source
- NVD
- EPSS
- EPSS 0.55 % · percentile 46 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Received
Description
In the Linux kernel, the following vulnerability has been resolved: openvswitch: fix GSO userspace truncation underflow OVS_ACTION_ATTR_TRUNC currently stores a delta from the original skb length in OVS_CB(skb)->cutlen. When a later userspace action segments a GSO skb, queue_gso_packets() reuses that delta for each smaller segment. A segment can then reach queue_userspace_packet() with cutlen greater than skb->len, underflowing the length passed to skb_zerocopy(). Store the maximum preserved length instead and bound each consumer against the current skb length. Use U32_MAX as the no-truncation sentinel so the value remains valid if skb geometry changes before a consumer handles it.
Weaknesses (CWE)
- CWE-191 — Integer Underflow (Wrap or Wraparound)
References
- https://git.kernel.org/stable/c/50a6a85f3d6b1d22d8436848606cdef5d2c490b4
- https://git.kernel.org/stable/c/2623c48cc3a8da9a1886fd8f65c0e348f4406fd6
- https://git.kernel.org/stable/c/e211b081901ffca76674082c73eeaed53524c369
- https://git.kernel.org/stable/c/a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855
- https://git.kernel.org/stable/c/fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc
- https://git.kernel.org/stable/c/100a23b1613e9218e0af654ef102352c713f0263
- https://git.kernel.org/stable/c/ea85dbcbe8d4056ecb54352f97743d138ea4c407
- https://git.kernel.org/stable/c/4032f8ed10fcb84d41c508dfb04be96589f78dfe
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | CRITICAL 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | Linux |
| CVSS 3.1 | CRITICAL 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-55504
- GCVE · GCVE-0-2026-68123
CERT-FR advisories
- CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1334 — Multiples vulnérabilités dans le noyau Linux de Red Hat · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1333 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1286 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1255 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1231 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1203 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1202 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1164 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1163 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1069 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1 < 50a6a85f3d6b1d22d8436848606cdef5d2c490b4 ; affected f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1 < 2623c48cc3a8da9a1886fd8f65c0e348f4406fd6 ; affected f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1 < e211b081901ffca76674082c73eeaed53524c369 ; affected f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1 < a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855 ; affected f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1 < fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc ; affected f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1 < 100a23b1613e9218e0af654ef102352c713f0263 |
| Linux · Linux | affected 4.8 ; unaffected 0 < 4.8 ; unaffected 5.10.265 ≤ 5.10.* ; unaffected 5.15.216 ≤ 5.15.* ; unaffected 6.1.183 ≤ 6.1.* ; unaffected 6.6.148 ≤ 6.6.* |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |