Categories
CVE-2025-38626 medium CVSS 5.5

Vulnerability in Linux kernel (CVE-2025-38626)

Summary

Vulnerability in Linux kernel (CVE-2025-38626). Risk of unauthorized operations or information disclosure.

Original description

The description as published by the source.

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

f2fs: fix to trigger foreground gc during f2fs_map_blocks() in lfs mode

w/ "mode=lfs" mount option, generic/299 will cause system panic as below:

------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:2835!
Call Trace:

f2fs_allocate_data_block+0x6f4/0xc50
f2fs_map_blocks+0x970/0x1550
f2fs_iomap_begin+0xb2/0x1e0
iomap_iter+0x1d6/0x430
__iomap_dio_rw+0x208/0x9a0
f2fs_file_write_iter+0x6b3/0xfa0
aio_write+0x15d/0x2e0
io_submit_one+0x55e/0xab0
__x64_sys_io_submit+0xa5/0x230
do_syscall_64+0x84/0x2f0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0010:new_curseg+0x70f/0x720

The root cause of we run out-of-space is: in f2fs_map_blocks(), f2fs may
trigger foreground gc only if it allocates any physical block, it will be
a little bit later when there is multiple threads writing data w/
aio/dio/bufio method in parallel, since we always use OPU in lfs mode, so
f2fs_map_blocks() does block allocations aggressively.

In order to fix this issue, let's give a chance to trigger foreground
gc in prior to block allocation in f2fs_map_blocks().

Source: NIST National Vulnerability Database NVD GitHub Advisory

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-2025-38626 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure. CVSS score: 5.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2025-38626" on the vendor's site.

CVE-2025-38626 (Linux kernel) — CVSS v3 5.5
Attack vector: local / no user interaction
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 Linux kernel.

📍 Affected scope

Check the vendor advisory for the affected versions of Linux kernel.

🔥 Severity

Severity: Medium (CVSS 5.5/10). Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to the patched release per vendor advisory.

🛡️ 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. Audit SBOM/dependencies to find affected services.

Response actions

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

  1. 1
    Identify exposure identify
    Audit SBOM/dependencies for affected components.

    資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。

  2. 2
    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":"4.8.0"},{"fixed":"5.15.209"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.167"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.102"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.42"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.15.10"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.16.0"},{"fixed":"6.16.1"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

References

We use cookies for analytics and ad measurement. This setting applies to all Game co., Ltd. sites. Details