CVE-2026-74736
Published: August 29, 2026Last modified: August 29, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_bpf: reject dev-bound programs bound to a different device cls_bpf_prog_from_efd() obtained a SCHED_CLS program via bpf_prog_get_type_dev() but never verified that a device-bound (offloaded) program's bound netdev matches the TC netdev the classifier is being attached to. This let a program loaded with prog_ifindex for device A be attached via cls_bpf + skip_sw to device B; deleting device A then destroyed the program's offload state while it was still attached to device B, triggering a netdevsim WARN (panic with panic_on_warn=1). Mirror the XDP attach path (net/core/dev.c) and reject the attach with -EINVAL when a dev-bound program's bound device does not match the target device.
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 | Not affected (6.1.33-r0) |
| 25 LTS | linux-lts | Vulnerable (6.12.103-r0) | |
| Stream | linux-lts | Fixed (6.18.46-r0) |
References
- https://git.kernel.org/stable/c/120977e2c096deea4e866e4273be9220b957c29e
- https://git.kernel.org/stable/c/5685bbbd3cbfbeb0de96a1d275a5ca073dfebb5e
- https://git.kernel.org/stable/c/adb3e7c26a51a10d94a241c6de7a81a2863dcacf
- https://git.kernel.org/stable/c/daf546ab5763ce6a18280cb4db060e836c515301
- https://git.kernel.org/stable/c/ec5a552f4b2d841c6c021752450716e1a9676661