CVE-2026-97964
In the Linux kernel, the following vulnerability has been resolved: ppp_synctty: ensure a writeable skb header ppp_sync_txmunge() checks headroom before prepending the address and control bytes, but does not ensure that the skb header is writable. A received skb can reach this function through PPP channel bridging without passing through ppp_start_xmit(), which calls skb_cow_head(). For example, a PPPoE frame may share its buffer with a clone queued to an AF_PACKET socket. If it is bridged to a synchronous tty channel, the address/control bytes can overwrite data still visible to that socket. Use skb_cow_head() to ensure both sufficient headroom and a writable header.
Affected versions
Linux kernel versions
5.11
and later are affected. Fixed in
5.15.222,
6.1.189,
6.6.158,
6.12.111,
6.18.53,
7.2.7,
7.3-rc3
and their respective stable series.
References
7 totalFrequently asked questions
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What is CVE-2026-97964?
CVE-2026-97964 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 5.11 onward and has been patched in 5.15.222, 6.1.189, 6.6.158 and others. CVE-2026-97964 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-97964?
Yes. CVE-2026-97964 has been patched. Fixed versions include 5.15.222, 6.1.189, 6.6.158 and others. If you are running Linux kernel 5.11 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-97964 actively exploited?
No. CVE-2026-97964 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.