CVE-2025-71161
Medium
Elevated severity or exploit probability.
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | N | None |
| Integrity | N | None |
| Availability | H | High |
Timeline
- 2026-01-23 — Published (NVD)
- 2026-07-30 — Last modified (NVD)
Description
In the Linux kernel, the following vulnerability has been resolved: dm-verity: disable recursive forward error correction There are two problems with the recursive correction: 1. It may cause denial-of-service. In fec_read_bufs, there is a loop that has 253 iterations. For each iteration, we may call verity_hash_for_block recursively. There is a limit of 4 nested recursions - that means that there may be at most 253^4 (4 billion) iterations. Red Hat QE team actually created an image that pushes dm-verity to this limit - and this image just makes the udev-worker process get stuck in the 'D' state. 2. It doesn't work. In fec_read_bufs we store data into the variable "fio->bufs", but fio bufs is shared between recursive invocations, if "verity_hash_for_block" invoked correction recursively, it would overwrite partially filled fio->bufs.
Affected
References
- https://git.kernel.org/stable/c/232948cf600fba69aff36b25d85ef91a73a35756
- https://git.kernel.org/stable/c/4220cb37406915c926c0e4a3dbab77cd9cceeb1e
- https://git.kernel.org/stable/c/897d9006e75f46f8bd7df78faa424327ae6a4bcf
- https://git.kernel.org/stable/c/8b821ca892cfeeaf0bedc9fc72717294f67144d5
- https://git.kernel.org/stable/c/d9f3e47d3fae0c101d9094bc956ed24e7a0ee801
- https://git.kernel.org/stable/c/e227d2b229c7529bd98d348efc55262ccf24ab35
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html