Skip to content
major vulnerability· requires attention

Linux kernel bug in netfilter synproxy causes remote kernel memory corruption on network path; affects widely deployed Linux systems, routers, and firewalls and can disrupt infrastructure.

Networks

CVE-2026-64007

9.8
Critical
EPSS 0.51%Patch availableJul 21, 2026

Linux netfilter synproxy flaw allows kernel memory corruption via crafted TCP SYN packets

common questions

Is CVE-2026-64007 being exploited?

Not confirmed. CVE-2026-64007 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 0.51% probability of exploitation in the next 30 days.

How severe is CVE-2026-64007?

CVE-2026-64007 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-2026-64007?

Yes. A fix has been recorded for CVE-2026-64007. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.

What does CVE-2026-64007 affect?

CVE-2026-64007 affects Linux kernel (netfilter synproxy module), Routers/firewalls using synproxy, Linux servers and network appliances. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.

What should I do about CVE-2026-64007?

Apply vendor/kernel updates and reboot affected hosts; restrict synproxy if not required.

Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.

executive summary
technical analysis
affected
Linux kernel (netfilter synproxy module)Routers/firewalls using synproxyLinux servers and network appliances
impact

Remote-crafted TCP SYNs can trigger kernel memory corruption, causing crashes or enabling privilege escalation/remote code execution.

action required

Patch when possible

affected versions
Linux Linux
  • affected>= 48b1de4c110a7afa4b85862f6c75af817db26fad and < 9902a1058992de5d95656b64a3bd95c077f7ba2c
  • affected>= 48b1de4c110a7afa4b85862f6c75af817db26fad and < d3019c61799adc21811af4b521f11f3dc77f8e04
  • affected>= 48b1de4c110a7afa4b85862f6c75af817db26fad and < dd206819f210522579010d889d45a9530bb494bc
  • affected>= 48b1de4c110a7afa4b85862f6c75af817db26fad and < af2c22ccb1f621aff487ff47a040e38e058541e7
  • affected>= 48b1de4c110a7afa4b85862f6c75af817db26fad and < c7f945f7da097245a2f8ed7775ce48421047ee96
  • affected>= 48b1de4c110a7afa4b85862f6c75af817db26fad and < f0fea2b6d5453a11ad11713bbf37561b9b3a7edf
  • affected>= 48b1de4c110a7afa4b85862f6c75af817db26fad and < a91887a5b6ee4b98dfbf1db657ed2b879430149e
  • affected>= 48b1de4c110a7afa4b85862f6c75af817db26fad and < 92170e6afe927ab2792a3f71902845789c8e31b1
  • affected3.12
vendor says fixed in< 3.12, >= 5.10.259 and <= 5.10.*, >= 5.15.210 and <= 5.15.*, >= 6.1.176 and <= 6.1.*, >= 6.6.143 and <= 6.6.*, >= 6.12.93 and <= 6.12.*, >= 6.18.35 and <= 6.18.*, >= 7.0.12 and <= 7.0.*, >= 7.1 and <= *

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.

how to fix
Remediation steps are tailored for users whose stack is affected. Add this technology to your stack to see the fix checklist.
references
get alerted

Track only the vulnerabilities that affect your infrastructure.

start for free