CVE-2026-45929 (GCVE-0-2026-45929)

Vulnerability from cvelistv5 – Published: 2026-05-27 12:17 – Updated: 2026-08-05 12:28
VLAI
Title
ovpn: fix possible use-after-free in ovpn_net_xmit
Summary
In the Linux kernel, the following vulnerability has been resolved: ovpn: fix possible use-after-free in ovpn_net_xmit When building the skb_list in ovpn_net_xmit, skb_share_check will free the original skb if it is shared. The current implementation continues to use the stale skb pointer for subsequent operations: - peer lookup, - skb_dst_drop (even though all segments produced by skb_gso_segment will have a dst attached), - ovpn_peer_stats_increment_tx. Fix this by moving the peer lookup and skb_dst_drop before segmentation so that the original skb is still valid when used. Return early if all segments fail skb_share_check and the list ends up empty. Also switch ovpn_peer_stats_increment_tx to use skb_list.next; the next patch fixes the stats logic.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 08857b5ec5d91d83e69e40a36554a8c7557b7301 , < 3e4fbcb4e078915367ba5576cd70d76dbc970f95 (git)
Affected: 08857b5ec5d91d83e69e40a36554a8c7557b7301 , < 442915c96a9bff1c7080e2aedabb1c03faa28d81 (git)
Affected: 08857b5ec5d91d83e69e40a36554a8c7557b7301 , < a5ec7baa44ea3a1d6aa0ca31c0ad82edf9affe41 (git)
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Linux Linux Affected: 6.16
Unaffected: 0 , < 6.16 (semver)
Unaffected: 6.18.14 , ≤ 6.18.* (semver)
Unaffected: 6.19.4 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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}



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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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