CVE-2026-80977
Published: September 15, 2026Last modified: September 15, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: net: skbuff: don't touch shared zerocopy state in skb_tx_error() skb_tx_error() completes the zerocopy uarg and clears SKBFL_ALL_ZEROCOPY, and skb_zcopy_downgrade_managed() clears SKBFL_MANAGED_FRAG_REFS. Both live in skb_shinfo(), which every clone shares, while the caller only owns the reference it is about to drop. Through a clone it tells the producer its pages are free and drops SKBFL_SHARED_FRAG for an skb that is still in flight. Open vSwitch reaches this with a non-last OVS_ACTION_ATTR_RECIRC: clone_execute() sends a skb_clone() into ovs_dp_process_packet() while do_execute_actions() keeps forwarding the original, and skb_clone() does not privatise the frags here -- skb_orphan_frags() returns early on SKBFL_DONT_ORPHAN. A flow miss on the clone then strips the marker from the packet still being forwarded, and a later local ESP delivery decrypts in place over frags it does not own privately. Skip it for a cloned skb. Nothing is lost: skb_release_data() clears the zerocopy state once the last reference to the shared data goes.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.8 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Vulnerable (6.1.182-r0) |
| 25 LTS | linux-lts | Vulnerable (6.12.103-r0) | |
| Stream | linux-lts | Vulnerable (6.18.46-r0) |
References
- https://git.kernel.org/stable/c/0370da114a9bc044e248b85c6809d1b5e0c1f7f9
- https://git.kernel.org/stable/c/15aa81b390d401abf4b8211042470e9e92e3b7fb
- https://git.kernel.org/stable/c/288f9970670841044ab030104fa6b6ed159949d0
- https://git.kernel.org/stable/c/363c4252ffc473a0203e91b83ede5519dfb8bd07
- https://git.kernel.org/stable/c/6493165034bca14033bf49c9cec7b45e97a91497
- https://git.kernel.org/stable/c/6ec22afc82a3cae07ade0a6ec361ae2532128ff5
- https://git.kernel.org/stable/c/b4452349dcf4d561e13be768d5d278de58248930
- https://git.kernel.org/stable/c/f66bdb1cc0fcd227a062378f8be0b5873aa5600a