CVE-2026-72347
Published: August 18, 2026Last modified: August 18, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_connmark: reject invalid shift parameters Revision 2 of the CONNMARK target accepts user-controlled shift parameters and applies them to 32-bit mark values in connmark_tg_shift(). A shift_bits value of 32 or more triggers an undefined-shift bug when the rule is evaluated. Invalid shift_dir values are also accepted and silently fall back to the left-shift path. Reject invalid revision-2 shift parameters in connmark_tg_check() so malformed rules fail at installation time, before they can reach the packet path.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.3 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | LOW |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.182-r0) |
| 25 LTS | linux-lts | Fixed (6.12.103-r0) | |
| Stream | linux-lts | Fixed (6.18.43-r0) |
References
- https://git.kernel.org/stable/c/1b47026fb4b35bac850ad6e8a4ad7fc018e09ebc
- https://git.kernel.org/stable/c/230173cc6105bdfb2696d37e6e56687b003fbe63
- https://git.kernel.org/stable/c/4eef84b09a3836919360c4232b0f16651a155eec
- https://git.kernel.org/stable/c/8ace320ac4416f5e5fbcd065309fb2dfcce787b0
- https://git.kernel.org/stable/c/9657bb11a6376ab0a79f05d433713d6944111e9d
- https://git.kernel.org/stable/c/c3fa852d117b3fda72265e4230e3967db4a74fcf
- https://git.kernel.org/stable/c/d8ce63d928b457fba7ed1e302492dfd32293671c