Skip to main content
VulnerabilityPublished Updated

CVE-2026-64564: Linux kernel · Use After Free

Affects Linux kernelSource CVE Database V5

0

Not known to be exploited · CVSS 9.8 Critical · fixed in fedeb4468987bcaff85fe3061de5ae052d414740 : patch Linux kernel as a priority.

Data as of 26 Oct 2026, 13:47 UTC

CVSS 3.1 base score
9.8Critical
How severe the flaw is on the 0–10 CVSS scale.
EPSS
1.4% chance of exploitation in 30 days – higher than 72% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CISA SSVC
Exploitation
No evidence of active exploitation and no public proof of concept
Automatable
Attackers can reliably automate steps 1–4 of the kill chain
Technical impact
Total control over the software or total information disclosure

CISA SSVC assessment, 2026-10-16.

Patch
Available – fixed in fedeb4468987bcaff85fe3061de5ae052d414740, d136b29bf91dd8e3161281b87de597b7311d9462, a63afa1f9b12d5293cbe0b77fd45dc0632533a13 +5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 4 Aug 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ 42e30bf3463cd37d73839376662cb79b4d5c416c, < fedeb4468987bcaff85fe3061de5ae052d414740
Fixed in
  • fedeb4468987bcaff85fe3061de5ae052d414740
LinuxLinuxAffected
  • ≥ 42e30bf3463cd37d73839376662cb79b4d5c416c, < d136b29bf91dd8e3161281b87de597b7311d9462
Fixed in
  • d136b29bf91dd8e3161281b87de597b7311d9462
LinuxLinuxAffected
  • ≥ 42e30bf3463cd37d73839376662cb79b4d5c416c, < a63afa1f9b12d5293cbe0b77fd45dc0632533a13
Fixed in
  • a63afa1f9b12d5293cbe0b77fd45dc0632533a13
LinuxLinuxAffected
  • ≥ 42e30bf3463cd37d73839376662cb79b4d5c416c, < a9ce31be4cb1a5dd82b3e0a1d0c3e7cbdcd31293
Fixed in
  • a9ce31be4cb1a5dd82b3e0a1d0c3e7cbdcd31293
LinuxLinuxAffected
  • ≥ 42e30bf3463cd37d73839376662cb79b4d5c416c, < 85aca407c560aba81b5ce9d3d6cf94c74077d19b
Fixed in
  • 85aca407c560aba81b5ce9d3d6cf94c74077d19b
LinuxLinuxAffected
  • ≥ 42e30bf3463cd37d73839376662cb79b4d5c416c, < 74e8f3e7114f0e26d1b2c4c048044db9fcc27603
Fixed in
  • 74e8f3e7114f0e26d1b2c4c048044db9fcc27603

Description

In the Linux kernel, the following vulnerability has been resolved: sctp: don't free the ASCONF's own transport in DEL-IP processing sctp_process_asconf() caches the transport the ASCONF chunk is processed against in asconf->transport (== chunk->transport, set once in sctp_rcv()). For an ASCONF located through its Address Parameter by __sctp_rcv_asconf_lookup(), that cached transport corresponds to the Address Parameter, which need not be the packet's source address. sctp_process_asconf_param() rejects a DEL-IP for the packet source address (ADDIP D8, SCTP_ERROR_DEL_SRC_IP), but nothing protects asconf->transport. A single ASCONF can therefore carry, in order: [Address Parameter L] [DEL-IP L] [DEL-IP 0.0.0.0] where L differs from the source. The DEL-IP for L passes the D8 check and calls sctp_assoc_rm_peer() on the transport that asconf->transport still points at, freeing it (RCU-deferred). The following wildcard DEL-IP then reuses the now-dangling asconf->transport in sctp_assoc_set_primary() and sctp_assoc_del_nonprimary_peers(): set_primary() dereferences the freed transport (->ipaddr, ->state) and plants the dangling pointer into asoc->peer.primary_path / active_path, and del_nonprimary_peers(), keeping only the pointer that is no longer on the list, removes every real transport, leaving the association with a transport_count of 0 and primary_path/active_path pointing at freed memory. Reject a DEL-IP that targets the transport the ASCONF is being processed against, mirroring the existing source-address guard, so the wildcard branch can never reuse a freed transport.

References

Community reviews

Loading reviews…