Remote kernel memory-corruption in Linux netfilter conntrack SIP affects widely deployed Linux kernels; can disrupt infrastructure and enable RCE or system crashes.
CVE-2026-74569
Linux kernel netfilter SIP conntrack bug allows remote kernel memory corruption.
Is CVE-2026-74569 being exploited?
Not confirmed. CVE-2026-74569 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 0.39% probability of exploitation in the next 30 days.
How severe is CVE-2026-74569?
CVE-2026-74569 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-2026-74569?
Yes. A fix has been recorded for CVE-2026-74569. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-74569 affect?
CVE-2026-74569 affects Linux kernel (netfilter nf_conntrack_sip). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-74569?
Apply vendor/kernel updates immediately or disable nf_conntrack_sip if unused.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attackers sending crafted SIP/TCP packets can trigger kernel use-after-free, causing crashes and potential remote code execution/privilege escalation.
Immediate action required
- affected>= f5b321bd37fbec9188feb1f721ab46a5ac0b35da and < ed1f9be6dc8e2e280b8725e44ccdc6e0cd38640d
- affected>= f5b321bd37fbec9188feb1f721ab46a5ac0b35da and < 1b0843f9e9b9b0b9b4b70d143b67e58163c85b2c
- affected>= f5b321bd37fbec9188feb1f721ab46a5ac0b35da and < 32d4abc8923b0d4046fd63ad6e4917872e44eb6d
- affected>= f5b321bd37fbec9188feb1f721ab46a5ac0b35da and < 63eea41759fd682229c14e0a2205802b46d106f3
- affected>= f5b321bd37fbec9188feb1f721ab46a5ac0b35da and < c97621a110e386b2dd69e276eb699e1d3cec581d
- affected>= f5b321bd37fbec9188feb1f721ab46a5ac0b35da and < f74554e67ccf04d1fa71069e8c9afa2717e40716
- affected>= f5b321bd37fbec9188feb1f721ab46a5ac0b35da and < ef5e2c6555d2bb52dfe0e4053a8c6193f9d83b64
- affected>= f5b321bd37fbec9188feb1f721ab46a5ac0b35da and < db3d0e0e5d4bc5ab4fe445b9f413d1b486508ca5
- affected2.6.34
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.