CVE-2026-97964ppp_synctty: ensure a writeable skb header
- —Not scoredno CVSS score yet
- 0.17%Exploitation in 30 daysEPSS · top 93% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By Linux
Published
- 24 days later
· 24 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.17% · top 93% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected 4cf476ced45d7f12df30a68e833b263e7a2202d1 – < 25e03eeead2c49748c7582dfb64c205f93a42d00
- affected 4cf476ced45d7f12df30a68e833b263e7a2202d1 – < a256f9925288ef47de8febed5c38d5cc21340211
- affected 4cf476ced45d7f12df30a68e833b263e7a2202d1 – < 7953946f68262a8bb137aa101249adef6e029652
- affected 4cf476ced45d7f12df30a68e833b263e7a2202d1 – < 3af7797fbabc84992e0ca5ad2bc0ca8537d053ef
- affected 4cf476ced45d7f12df30a68e833b263e7a2202d1 – < 0996c3e6bcc6ae08cb371ed43648c9f7f748ae6e
- affected 4cf476ced45d7f12df30a68e833b263e7a2202d1 – < 15d0a6c9a42df2d745c37510dba828f6dbe60d9f
- affected 4cf476ced45d7f12df30a68e833b263e7a2202d1 – < 8aaeb56aff2a557a88f83ae866da2c91ad247e59
- affected 5.11
- unaffected < 5.11
- unaffected 5.15.222 – ≤ 5.15.*
- unaffected 6.1.189 – ≤ 6.1.*
- unaffected 6.6.158 – ≤ 6.6.*
- unaffected 6.12.111 – ≤ 6.12.*
- unaffected 6.18.53 – ≤ 6.18.*
- unaffected 7.2.7 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References7
- https://git.kernel.org/stable/c/25e03eeead2c49748c7582dfb64c205f93a42d00 (opens in a new tab)
- https://git.kernel.org/stable/c/a256f9925288ef47de8febed5c38d5cc21340211 (opens in a new tab)
- https://git.kernel.org/stable/c/7953946f68262a8bb137aa101249adef6e029652 (opens in a new tab)
- https://git.kernel.org/stable/c/3af7797fbabc84992e0ca5ad2bc0ca8537d053ef (opens in a new tab)
- https://git.kernel.org/stable/c/0996c3e6bcc6ae08cb371ed43648c9f7f748ae6e (opens in a new tab)
- https://git.kernel.org/stable/c/15d0a6c9a42df2d745c37510dba828f6dbe60d9f (opens in a new tab)
- https://git.kernel.org/stable/c/8aaeb56aff2a557a88f83ae866da2c91ad247e59 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-86818 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-97964)Record last updated .