Affects widely used Linux kernel; critical DoS via kernel panic from crafted IPv6 IOAM packets.
CVE-2026-43186
Linux kernel IOAM6 heap overflow via crafted IPv6 packet.
Is CVE-2026-43186 being exploited?
Not confirmed. CVE-2026-43186 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 0.64% probability of exploitation in the next 30 days.
How severe is CVE-2026-43186?
CVE-2026-43186 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-2026-43186?
Yes. A fix has been recorded for CVE-2026-43186. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-43186 affect?
CVE-2026-43186 affects Linux kernel. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-43186?
Apply patched kernel; update to fixed release
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Kernel heap overflow can crash the host via crafted IPv6 IOAM data on receive path.
Patch when possible
- affected>= 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 and < f4d9d4b8fd839719d564651671e24c62c545c23b
- affected>= 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 and < fb3c662fafebc5b9d74417ed1de8759f6bb72143
- affected>= 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 and < 632d233cf2e64a46865ae2c064ae3c9df7c8864f
- affected>= 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 and < 0591d6509c2ff13f09ea2998434aba0c0472e978
- affected>= 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 and < e90346a2f1e8917d5760a44a1f61c44e3b36d96b
- affected>= 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 and < ea3632aefc04205436868541638e26f4a74d5637
- affected>= 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 and < 6db8b56eed62baacaf37486e83378a72635c04cc
- affected5.15
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.