CVE-2026-53089
Published: June 26, 2026Last modified: June 26, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix use-after-free in offloaded map/prog info fill When querying info for an offloaded BPF map or program, bpf_map_offload_info_fill_ns() and bpf_prog_offload_info_fill_ns() obtain the network namespace with get_net(dev_net(offmap->netdev)). However, the associated netdev's netns may be racing with teardown during netns destruction. If the netns refcount has already reached 0, get_net() performs a refcount_t increment on 0, triggering: refcount_t: addition on 0; use-after-free. Although rtnl_lock and bpf_devs_lock ensure the netdev pointer remains valid, they cannot prevent the netns refcount from reaching zero. Fix this by using maybe_get_net() instead of get_net(). maybe_get_net() uses refcount_inc_not_zero() and returns NULL if the refcount is already zero, which causes ns_get_path_cb() to fail and the caller to return -ENOENT -- the correct behavior when the netns is being destroyed.
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 (6.1.175-r0) |
| 25 LTS | linux-lts | Vulnerable (6.12.92-r0) | |
| Stream | linux-lts | Vulnerable (6.18.35-r1) |
References
- https://git.kernel.org/stable/c/1a2dc103e16448d022a77ad5fc3234641436c4b7
- https://git.kernel.org/stable/c/43d6848a2a6c92ccfd614d9f0bb6fd85b95dfa9d
- https://git.kernel.org/stable/c/5662dac41a3442aa378d7c405164903eb109fc05
- https://git.kernel.org/stable/c/642943ae5bdacabc8109dc4a5e0ebb4a6b99ef3e
- https://git.kernel.org/stable/c/85dc711f742b192eb97c0e00b521312f5a7a415e
- https://git.kernel.org/stable/c/a0c584fc18056709c8e047a82a6045d6c209f4ce
- https://git.kernel.org/stable/c/a51e7fbe94a87e236631a83973d4f558310b2cd2
- https://git.kernel.org/stable/c/fea55b034328feaafef75aee252f305e6f85a991