CVE-2025-21829Network attack vector

Kernel memory corruption via premature QP free

Published Mar 6, 2025 · Updated Aug 5, 2026

Use-after-free in Linux kernel RDMA/rxe allows remote attackers to corrupt kernel memory through Soft-RoCE QP teardown. The 200-jiffy cleanup timeout can expire while references remain, causing __rxe_cleanup to free struct rxe_qp and queue memory still used by packet tasks. Unauthenticated peers can control load and disconnect timing over UDP port 4791, enabling kernel-memory disclosure, writes, or repeatable crashes.

CVSS severity9.8
Critical
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Linux kernel RDMA/rxe allows remote attackers to corrupt kernel memory through Soft-RoCE QP teardown. The 200-jiffy cleanup timeout can expire while references remain, causing __rxe_cleanup to free struct rxe_qp and queue memory still used by packet tasks. Unauthenticated peers can control load and disconnect timing over UDP port 4791, enabling kernel-memory disclosure, writes, or repeatable crashes.

The record

CVE
CVE-2025-21829
Published
Mar 6, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 6, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <45e567800492088bc52c9abac35524b4d332a8f8
  2. Affected versionversion=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <720653309dd31c8a927ef5d87964578ad544980f
  3. Affected versionversion=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <7a2de8126ed3801f2396720e10a03cd546a3cea1
  4. Affected versionversion=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <a7d15eaecf0d6e13226db629ae2401c8c02683e5
  5. Affected versionversion=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <edc4ef0e0154096d6c0cf5e06af6fc330dbad9d1
  6. Affected versionversion=6.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <45e567800492088bc52c9abac35524b4d332a8f8; version=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <720653309dd31c8a927ef5d87964578ad544980f; version=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <7a2de8126ed3801f2396720e10a03cd546a3cea1; version=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <a7d15eaecf0d6e13226db629ae2401c8c02683e5; version=215d0a755e1bcd92cbe6a71a21194ce7c82ec106 <edc4ef0e0154096d6c0cf5e06af6fc330dbad9d1; version=6.0

Published CVSS scores

9.8Linux Kernel CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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