CVE-2026-64000
Linux kernel hsr TLV OOB vulnerability allows kernel memory corruption or crash.
Is CVE-2026-64000 being exploited?
Not confirmed. CVE-2026-64000 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 0.49% probability of exploitation in the next 30 days.
How severe is CVE-2026-64000?
CVE-2026-64000 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-2026-64000?
Yes. A fix has been recorded for CVE-2026-64000. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-64000 affect?
CVE-2026-64000 affects Linux kernel (hsr module), Linux distributions with affected kernels, Industrial/embedded devices using HSR. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-64000?
Apply kernel/vendor updates immediately; or unload/disable hsr and block HSR traffic until patched.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Crafted HSR supervision frames can trigger out-of-bounds kernel memory access, causing crash (DoS) or potential remote code execution.
Immediate action required
- affected>= eafaa88b3eb7f28aecb222281655473431d3ef2e and < 09a37dca090c55ffb1a33f52d8667f1c2367ef48
- affected>= eafaa88b3eb7f28aecb222281655473431d3ef2e and < a4b64f3e9c7b8259f7dd251a0313420ba7c01852
- affected>= eafaa88b3eb7f28aecb222281655473431d3ef2e and < 71c986c0ba45b7dc574fae27c83e7b6671556f37
- affected>= eafaa88b3eb7f28aecb222281655473431d3ef2e and < fbd0662f9c9a66e8cc3df3099cca8ed6d3837cc7
- affected>= eafaa88b3eb7f28aecb222281655473431d3ef2e and < 78607a6854a22a2502f68092202e75a39af4865d
- affected>= eafaa88b3eb7f28aecb222281655473431d3ef2e and < f229426072fc865654a60978bb7fda790a051ff3
- affected5.16
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.