Widely deployed Linux kernel mlx5e/XDP path; critical infrastructure impact and potential disruption.
CVE-2026-43465
Linux mlx5e XDP frag counting flaw may cause negative reference counts.
Is CVE-2026-43465 being exploited?
Not confirmed. CVE-2026-43465 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.41% probability of exploitation in the next 30 days.
How severe is CVE-2026-43465?
CVE-2026-43465 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-43465?
Yes. A fix has been recorded for CVE-2026-43465. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-43465 affect?
CVE-2026-43465 affects Linux kernel with mlx5e driver (Mellanox NICs). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-43465?
Update kernel/driver to patched version
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Kernel crash or memory error due to improper XDP fragment accounting in mlx5e driver.
Patch when possible
- affected>= 87bcef158ac1faca1bd7e0104588e8e2956d10be and < 7d7342a18fadcdb70a63b3c930dc63528ce51832
- affected>= 87bcef158ac1faca1bd7e0104588e8e2956d10be and < 043bd62f748bc9fd98154037aa598cffbd3c667c
- affected>= 87bcef158ac1faca1bd7e0104588e8e2956d10be and < db25c42c2e1f9c0d136420fff5e5700f7e771a6f
- affected8b051d7f530e8a5237da242fbeafef02fec6b813
- affectedcb9edd583e23979ee546981be963ad5f217e8b18
- affectedf2557d7fa38e9475b38588f5c124476091480f53
- affected>= 6.6.115 and < 6.7
- affected>= 6.12.56 and < 6.13
- affected>= 6.17.6 and < 6.18
- affected6.18
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.