CVE-2026-31420Patch(linux / linux_kernel)

LOWCVSS 5.5 · MEDIUM

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Patch linux linux_kernel systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD description

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.

0.5/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-667

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • linux_kernel

Threat summary

  • Patch or workaround signal is available
  • 1 mentions across 1 observed day

What's happening

  • Patch or workaround mentioned in 1 signal
  • Technical details provided in 1 signal
  • 1 total mentions across 1 day

Affected systems

Vendors
Products
linux_kernel

1 version affected across 1 product

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-04-13: 1Patch / Workaround · 2026-04-13: 1Technical Details · 2026-04-13: 104-13
Signal classification1 categories
Patch
1100.0%
Referenced assets1 URL
By indicator
Full discourse1 post
  • CVE@CVEnew
    Patch

    CVE-2026-31420 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_i… https://www.cve.org/CVERecord?id=CVE-2026-31420

    Post summary

    CVE-2026-31420 is a Linux kernel vulnerability involving an OOM panic triggered by a zero test interval in bridge MRP, which has already been fixed in the kernel. The text confirms a patch was applied but contains no exploitation details.

    00000216
    57.1K followersView on X
CPE platform detail7 entries

7 of 7 entries

PartVendorProductVersionTarget SWTarget HW
OSlinuxlinux_kernel---
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--
OSlinuxlinux_kernel7.0--

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