Answer in brief
CVE-2026-31420 records a Medium severity (CVSS 5.5) vulnerability in bridge: mrp: reject zero test interval to avoid OOM panic. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=20f6a05ef63594feb0c6dfbd629da0448b43124d <610073ffb77ffd2b5eca182d2ac264de4834a175 || >=20f6a05ef63594feb0c6dfbd629da0448b43124d <ec8850be9b2b3beac1c7967d95f169dd2785979d || >=20f6a05ef63594feb0c6dfbd629da0448b43124d <1ec86b4b9e28170a2565cf36f0e6e2b96b55134d || >=20f6a05ef63594feb0c6dfbd629da0448b43124d <2120bd8546cd6a63c558d135773aa8f41c8259fc || >=20f6a05ef63594feb0c6dfbd629da0448b43124d <630a15a31c2034b5b697f4aabc769b9d80d82446 || >=20f6a05ef63594feb0c6dfbd629da0448b43124d <e8ec80430bfa520e7352155d6ac632e527cba7aa || >=20f6a05ef63594feb0c6dfbd629da0448b43124d <c9bc352f716d1bebfe43354bce539ec2d0223b30 || >=20f6a05ef63594feb0c6dfbd629da0448b43124d <fa6e24963342de4370e3a3c9af41e38277b74cf3 | 610073ffb77ffd2b5eca182d2ac264de4834a175, ec8850be9b2b3beac1c7967d95f169dd2785979d, 1ec86b4b9e28170a2565cf36f0e6e2b96b55134d, 2120bd8546cd6a63c558d135773aa8f41c8259fc, 630a15a31c2034b5b697f4aabc769b9d80d82446, e8ec80430bfa520e7352155d6ac632e527cba7aa, c9bc352f716d1bebfe43354bce539ec2d0223b30, fa6e24963342de4370e3a3c9af41e38277b74cf3 |
| Linux/Linuxgeneric | 5.8 | Not reported |
Published upstream
Apr 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 14, 2026
In the Linux kernel, the following vulnerability has been resolved: bridge: mrp: reject zero test interval to avoid OOM panic br_mrp_start_test() and br_mrp_start_in_test() accept the user-supplied interval value from netlink without validation. When interval is 0, usecs_to_jiffies(0) yields 0, causing the delayed work (br_mrp_test_work_expired / br_mrp_in_test_work_expired) to reschedule itself with zero delay. This creates a tight loop on system_percpu_wq that allocates and transmits MRP test frames at maximum rate, exhausting all system memory and causing a kernel panic via OOM deadlock. The same zero-interval issue applies to br_mrp_start_in_test_parse() for interconnect test frames. Use NLA_POLICY_MIN(NLA_U32, 1) in the nla_policy tables for both IFLA_BRIDGE_MRP_START_TEST_INTERVAL and IFLA_BRIDGE_MRP_START_IN_TEST_INTERVAL, so zero is rejected at the netlink attribute parsing layer before the value ever reaches the workqueue scheduling code. This is consistent with how other bridge subsystems (br_fdb, br_mst) enforce range constraints on netlink attributes.
Quoted source text, attributed separately from HOL analysis.