CVE-2026-64045ovpn: tcp - use cached peer pointer in ovpn_tcp_close()
- 8.4HighCVSS base score
- 0.19%Exploitation in 30 daysEPSS · top 91% 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: ovpn: tcp - use cached peer pointer in ovpn_tcp_close() ovpn_tcp_close() loads the ovpn_socket via rcu_dereference_sk_user_data() under rcu_read_lock(), takes a reference on sock->peer, caches the peer pointer in a local, and drops the read lock. It then passes sock->peer (rather than the cached local) to ovpn_peer_del(), re-dereferencing the ovpn_socket after the RCU read section has ended. Unlike ovpn_tcp_sendmsg(), which uses the same "load under RCU, use after unlock" pattern but is protected by lock_sock() held across the function, ovpn_tcp_close() runs without the socket lock: inet_release() invokes sk_prot->close() without taking lock_sock first. ovpn_socket_release() can therefore complete its kref_put -> detach -> synchronize_rcu -> kfree(sock) sequence concurrently, in the window after ovpn_tcp_close() drops rcu_read_lock() but before it dereferences sock->peer. The synchronize_rcu() in ovpn_socket_release() protects readers that use the dereferenced pointer inside the RCU read section, not those that escape the pointer to a local and use it afterwards. A reproducer follows the pattern of commit 94560267d6c4 ("ovpn: tcp - don't deref NULL sk_socket member after tcp_close()"): trigger a peer removal (keepalive expiration or netlink OVPN_CMD_DEL_PEER) at the same moment userspace closes the TCP fd. That commit fixed the detach-side of the same race window; this one fixes the close-side at a different victim. Tighten the entry block to read sock->peer exactly once into the cached peer local, and route all subsequent uses (the hold check, the ovpn_peer_del() call, and the prot->close() invocation) through that local. sock->peer is only ever written once in ovpn_socket_new() under lock_sock(), before rcu_assign_sk_user_data() publishes the ovpn_socket, and is never reassigned afterwards - but the previous multi-read pattern made that invariant implicit rather than explicit. The same multi-read shape exists in ovpn_tcp_recvmsg(), ovpn_tcp_sendmsg(), ovpn_tcp_data_ready() and ovpn_tcp_write_space(); those will be cleaned up via a dedicated helper in a follow-up net-next series.
Timeline
ID reserved
By Linux
Published
- 17 days later
· 17 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
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High8.4 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | High8.4 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.19% · top 91% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.4.
Affected products
- affected 11851cbd60ea1e5abbd97619d69845ead99303d6 – < e5460eb7238c19d651a9b22b2378b587033a4095
- affected 11851cbd60ea1e5abbd97619d69845ead99303d6 – < d3ef441907fca7c340979e577a3db3bb634bf166
- affected 11851cbd60ea1e5abbd97619d69845ead99303d6 – < 775d8d7ad02aa345e1588424a6a8b9ae49fb9012
- affected 6.16
- unaffected < 6.16
- unaffected 6.18.34 – ≤ 6.18.*
- unaffected 7.0.11 – ≤ 7.0.*
- unaffected 7.1 – ≤ *
References
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-2026-45618 (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)
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[](https://cveledger.app/cve/CVE-2026-64045)Record last updated .