CVE Intelligence
Medium Logic error

CVE-2025-21892 — RDMA/mlx5: Fix the recovery flow of the UMR QP

In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix the recovery flow of the UMR QP This patch addresses an issue in the recovery flow of the UMR QP, ensuring tasks do not get stuck, as highlighted by the call trace [1]. During recovery, before transitioning the QP to the RESET state, the software must wait for all outstanding WRs to complete. Failing to do so can cause the firmware to skip sending some flushed CQEs with errors and simply discard them upon the RESET, as per the IB specification. This race condition can result in lost CQEs and tasks becoming stuck. To resolve this, the patch sends a final WR which serves only as a barrier before moving the QP state to RESET. Once a CQE is received for that final WR, it guarantees that no outstanding WRs remain, making it safe to transition the QP to RESET and subsequently back to RTS, restoring proper functionality. Note: For the barrier WR, we simply reuse the failed and ready WR. Since the QP is in an error state, it will only receive IB_WC_WR_FLUSH_ERR. However, as it serves only as a barrier we don't care about its status. [1] INFO: task rdma_resource_l:1922 blocked for more than 120 seconds. Tainted: G W 6.12.0-rc7+ #1626 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:rdma_resource_l state:D stack:0 pid:1922 tgid:1922 ppid:1369 flags:0x00004004 Call Trace: <TASK> __schedule+0x420/0xd30 schedule+0x47/0x130 schedule_timeout+0x280/0x300 ? mark_held_locks+0x48/0x80 ? lockdep_hardirqs_on_prepare+0xe5/0x1a0 wait_for_completion+0x75/0x130 mlx5r_umr_post_send_wait+0x3c2/0x5b0 [mlx5_ib] ? __pfx_mlx5r_umr_done+0x10/0x10 [mlx5_ib] mlx5r_umr_revoke_mr+0x93/0xc0 [mlx5_ib] __mlx5_ib_dereg_mr+0x299/0x520 [mlx5_ib] ? _raw_spin_unlock_irq+0x24/0x40 ? wait_for_completion+0xfe/0x130 ? rdma_restrack_put+0x63/0xe0 [ib_core] ib_dereg_mr_user+0x5f/0x120 [ib_core] ? lock_release+0xc6/0x280 destroy_hw_idr_uobject+0x1d/0x60 [ib_uverbs] uverbs_destroy_uobject+0x58/0x1d0 [ib_uverbs] uobj_destroy+0x3f/0x70 [ib_uverbs] ib_uverbs_cmd_verbs+0x3e4/0xbb0 [ib_uverbs] ? __pfx_uverbs_destroy_def_handler+0x10/0x10 [ib_uverbs] ? __lock_acquire+0x64e/0x2080 ? mark_held_locks+0x48/0x80 ? find_held_lock+0x2d/0xa0 ? lock_acquire+0xc1/0x2f0 ? ib_uverbs_ioctl+0xcb/0x170 [ib_uverbs] ? __fget_files+0xc3/0x1b0 ib_uverbs_ioctl+0xe7/0x170 [ib_uverbs] ? ib_uverbs_ioctl+0xcb/0x170 [ib_uverbs] __x64_sys_ioctl+0x1b0/0xa70 do_syscall_64+0x6b/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f99c918b17b RSP: 002b:00007ffc766d0468 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffc766d0578 RCX: 00007f99c918b17b RDX: 00007ffc766d0560 RSI: 00000000c0181b01 RDI: 0000000000000003 RBP: 00007ffc766d0540 R08: 00007f99c8f99010 R09: 000000000000bd7e R10: 00007f99c94c1c70 R11: 0000000000000246 R12: 00007ffc766d0530 R13: 000000000000001c R14: 0000000040246a80 R15: 0000000000000000 </TASK>

Published Mar 27, 2025 · Updated Oct 21, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+1
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.17%
ahead of 6% of scored CVEs · Oct 26, 2026
Affects
Linux
Linux and 1 more
CVSS base
4.7
Medium · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
  2. Apply the fixed version or the patch documented under Remediation.
  3. Search available logs for exploit probes matching the vulnerability class (logic error), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Linux Linux ≥ 158e71bb69e368b8b33e8b7c4ac8c111da0c1ae2 and < 6088e11c9aed12ecc8df465bdd334e60b75999a9≥ 158e71bb69e368b8b33e8b7c4ac8c111da0c1ae2 and < 3e3bf255992cc02404e9d209b127c1c9944239cf≥ 158e71bb69e368b8b33e8b7c4ac8c111da0c1ae2 and < 1d2b84d8d054313deed2b2fcafe1168bbcb9e99f≥ 158e71bb69e368b8b33e8b7c4ac8c111da0c1ae2 and < d97505baea64d93538b16baf14ce7b8c1fbad746version d8f7bff9a42627d37f4ecffeb01e44db42167175≥ 5.19.10 and < 5.20version 6.0 Vulnerable CVE Program (cve.org) e CISA ADP
Linux Linux Kernel ≥ 5.19.10 and < 6.12.18≥ 6.13 and < 6.13.6version 6.14-rc1version 6.14-rc2version 6.14-rc3version 6.14-rc4 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Local
Attack complexity
High
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
4.7 CVSS 3.1 Medium 1.0 3.6 nvd@nist.gov via NIST National Vulnerability Database
4.7 CVSS 3.1 Medium — — GitHub, Inc. via GitHub Security Advisories
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-362 · Race Condition

Other CVEs with this weakness →

EPSS over time FIRST

Oct 20, 2026 → Oct 26, 2026 · 7 reading(s) · max 0.17%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
endpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · linux/linux
    Oct 21, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 21, 2026
  • Fix documented
    Oct 21, 2026 · NIST National Vulnerability Database
  • Affected products added · linux/linux kernel
    Oct 21, 2026 · NIST National Vulnerability Database
  • CVSS changed · 4.7
    Oct 21, 2026 · NIST National Vulnerability Database
  • Source status changed · → Modified
    Oct 21, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 21, 2026 · Alertas do Telegram
  • 2025
  • CVE published
    Mar 27, 2025 · Linux

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 21, 2026 – Oct 21, 2026
  • 1× Official description updated · Oct 21, 2026 – Oct 21, 2026

References

6 on the record

Elsewhere on this site

Linux
every CVE for this vendor
Logic error
same class
CWE-362
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-99092 riscv: patch: fix handling of bpf-jit execmem addresses 1d
  • CVE-2026-99093 mm: don't schedule deferred kernel page table freeing while booting 1d
  • CVE-2026-99095 drm/vc4: drain the hangcheck timer and works on V3D unbind 1d
  • CVE-2026-99096 io_uring/register: don't exempt disabled rings from task restrictions 1d
  • CVE-2026-99097 tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper() 1d
  • CVE-2026-99098 dm-integrity: fix buffer overflow in inline mode with large tag size 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No CISA SSVC assessment.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2025-21892 is "RDMA/mlx5: Fix the recovery flow of the UMR QP", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 4.7 describes technical severity. EPSS 0.17% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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