Vulnerability in Kernel (CVE-2025-39831)

Summary

Vulnerability in Kernel (CVE-2025-39831). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 6.12.45, 6.16.5 or later.

Original description

The description as published by the source.

In the Linux kernel, the following vulnerability has been resolved:

fbnic: Move phylink resume out of service_task and into open/close

The fbnic driver was presenting with the following locking assert coming
out of a PM resume:
[ 42.208116][ T164] RTNL: assertion failed at drivers/net/phy/phylink.c (2611)
[ 42.208492][ T164] WARNING: CPU: 1 PID: 164 at drivers/net/phy/phylink.c:2611 phylink_resume+0x190/0x1e0
[ 42.208872][ T164] Modules linked in:
[ 42.209140][ T164] CPU: 1 UID: 0 PID: 164 Comm: bash Not tainted 6.17.0-rc2-virtme #134 PREEMPT(full)
[ 42.209496][ T164] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-5.fc42 04/01/2014
[ 42.209861][ T164] RIP: 0010:phylink_resume+0x190/0x1e0
[ 42.210057][ T164] Code: 83 e5 01 0f 85 b0 fe ff ff c6 05 1c cd 3e 02 01 90 ba 33 0a 00 00 48 c7 c6 20 3a 1d a5 48 c7 c7 e0 3e 1d a5 e8 21 b8 90 fe 90 <0f> 0b 90 90 e9 86 fe ff ff e8 42 ea 1f ff e9 e2 fe ff ff 48 89 ef
[ 42.210708][ T164] RSP: 0018:ffffc90000affbd8 EFLAGS: 00010296
[ 42.210983][ T164] RAX: 0000000000000000 RBX: ffff8880078d8400 RCX: 0000000000000000
[ 42.211235][ T164] RDX: 0000000000000000 RSI: 1ffffffff4f10938 RDI: 0000000000000001
[ 42.211466][ T164] RBP: 0000000000000000 R08: ffffffffa2ae79ea R09: fffffbfff4b3eb84
[ 42.211707][ T164] R10: 0000000000000003 R11: 0000000000000000 R12: ffff888007ad8000
[ 42.211997][ T164] R13: 0000000000000002 R14: ffff888006a18800 R15: ffffffffa34c59e0
[ 42.212234][ T164] FS: 000…

Source: OSV.dev (Open Source Vulnerabilities) NVD OSV

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2025-39831 has been found in Kernel.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 6.12.45, 6.16.5 or later.
If unsure, ask your IT team or search "Kernel CVE-2025-39831" on the vendor's site.

CVE-2025-39831 (Kernel)
Attack vector: local / no user interaction
Patched: 6.12.45, 6.16.5 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (unclassified) exists in Kernel.

📍 Affected scope

Check the vendor advisory for the affected versions of Kernel.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 6.12.45, 6.16.5.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Kernel' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'Kernel' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で Kernel を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade Kernel to 6.12.45, 6.16.5
```
ステージング環境で 6.12.45, 6.16.5 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"6.11.0"},{"fixed":"6.12.45"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.16.5"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

BellSoft Alpaquita BELL-CVE-2025-39831 linux-lts Fixed in: 6.12.51-r0
Debian DEBIAN-CVE-2025-39831 linux Fixed in: 6.12.48-1
Ubuntu UBUNTU-CVE-2025-39831 linux-hwe-edge