Vulnerability in Kernel (CVE-2025-37865)

Summary

Vulnerability in Kernel (CVE-2025-37865). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 6.1.135, 6.6.88, 6.12.25, 6.14.4 or later.

Original description

The description as published by the source.

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

net: dsa: mv88e6xxx: fix -ENOENT when deleting VLANs and MST is unsupported

Russell King reports that on the ZII dev rev B, deleting a bridge VLAN
from a user port fails with -ENOENT:
https://lore.kernel.org/netdev/Z_lQXNP0s5-IiJzd@shell.armlinux.org.uk/

This comes from mv88e6xxx_port_vlan_leave() -> mv88e6xxx_mst_put(),
which tries to find an MST entry in &chip->msts associated with the SID,
but fails and returns -ENOENT as such.

But we know that this chip does not support MST at all, so that is not
surprising. The question is why does the guard in mv88e6xxx_mst_put()
not exit early:

if (!sid)
	return 0;

And the answer seems to be simple: the sid comes from vlan.sid which
supposedly was previously populated by mv88e6xxx_vtu_get().
But some chip->info->ops->vtu_getnext() implementations do not populate
vlan.sid, for example see mv88e6185_g1_vtu_getnext(). In that case,
later in mv88e6xxx_port_vlan_leave() we are using a garbage sid which is
just residual stack memory.

Testing for sid == 0 covers all cases of a non-bridge VLAN or a bridge
VLAN mapped to the default MSTI. For some chips, SID 0 is valid and
installed by mv88e6xxx_stu_setup(). A chip which does not support the
STU would implicitly only support mapping all VLANs to the default MSTI,
so although SID 0 is not valid, it would be sufficient, if we were to
zero-initialize the vlan structure, to fix the bug, due to the
coincidence that a test f…

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-2025-37865 has been found in Kernel.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 6.1.135, 6.6.88, 6.12.25, 6.14.4 or later.
If unsure, ask your IT team or search "Kernel CVE-2025-37865" on the vendor's site.

CVE-2025-37865 (Kernel)
Patched: 6.1.135, 6.6.88, 6.12.25, 6.14.4 — 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 6.1.135, 6.6.88, 6.12.25, 6.14.4.

🛡️ 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 6.1.135, 6.6.88, 6.12.25, 6.14.4
```
ステージング環境で 6.1.135, 6.6.88, 6.12.25, 6.14.4 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":"5.18.0"},{"fixed":"6.1.135"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.88"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.25"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.14.4"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

BellSoft Alpaquita BELL-CVE-2025-37865 linux-lts Fixed in: 6.1.140-r0
Debian DEBIAN-CVE-2025-37865 linux Fixed in: 6.1.135-1
Ubuntu UBUNTU-CVE-2025-37865 linux-hwe-edge