Affects widely used Linux kernel; potential remote exploitation via crafted ICMPv4 with CIPSO; high disruption risk across IT environments.
CVE-2026-43038
Linux kernel ICMPv6 CIPSO handling: crafted ICMPv4 may trigger memory issues.
Is CVE-2026-43038 being exploited?
Not confirmed. CVE-2026-43038 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 0.26% probability of exploitation in the next 30 days.
How severe is CVE-2026-43038?
CVE-2026-43038 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-2026-43038?
Yes. A fix has been recorded for CVE-2026-43038. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-43038 affect?
CVE-2026-43038 affects Linux kernel. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-43038?
Patch kernel, reboot, verify remediation.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attacker could abuse forged ICMPv4 with CIPSO to trigger unsafe inner IPv6 parsing, risking memory corruption or crash.
Patch when possible
- affected>= ca15a078bd907df5fc1c009477869c5cbde3b753 and < c438ba010171b70bad22fc18b1d5bdc3627476e8
- affected>= ca15a078bd907df5fc1c009477869c5cbde3b753 and < 0452b6526b2f54b2413b9cb4ff1ea2ac542c99c7
- affected>= ca15a078bd907df5fc1c009477869c5cbde3b753 and < a4437faf135da293d16fcc4cc607316742bd0ebb
- affected>= ca15a078bd907df5fc1c009477869c5cbde3b753 and < 3d5127d998de617b130aae96b138dba22ac6a8a7
- affected>= ca15a078bd907df5fc1c009477869c5cbde3b753 and < e41953e7d118e2702bcb217879c173d9d1d3cd4e
- affected>= ca15a078bd907df5fc1c009477869c5cbde3b753 and < a2edbb6393972a02114b6003953a5cef3104fada
- affected>= ca15a078bd907df5fc1c009477869c5cbde3b753 and < 1ceeebd5bd6d855b17a5df625109bfe29129d7cf
- affected>= ca15a078bd907df5fc1c009477869c5cbde3b753 and < 86ab3e55673a7a49a841838776f1ab18d23a67b5
- affected3.13
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.