Vulnerability in Linux kernel (CVE-2025-37752)
Summary
Vulnerability in Linux kernel (CVE-2025-37752). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
net_sched: sch_sfq: move the limit validation
It is not sufficient to directly validate the limit on the data that
the user passes as it can be updated based on how the other parameters
are changed.
Move the check at the end of the configuration update process to also
catch scenarios where the limit is indirectly updated, for example
with the following configurations:
tc qdisc add dev dummy0 handle 1: root sfq limit 2 flows 1 depth 1
tc qdisc add dev dummy0 handle 1: root sfq limit 2 flows 1 divisor 1
This fixes the following syzkaller reported crash:
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in net/sched/sch_sfq.c:203:6
index 65535 is out of range for type 'struct sfq_head[128]'
CPU: 1 UID: 0 PID: 3037 Comm: syz.2.16 Not tainted 6.14.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x201/0x300 lib/dump_stack.c:120
ubsan_epilogue lib/ubsan.c:231 [inline]
__ubsan_handle_out_of_bounds+0xf5/0x120 lib/ubsan.c:429
sfq_link net/sched/sch_sfq.c:203 [inline]
sfq_dec+0x53c/0x610 net/sched/sch_sfq.c:231
sfq_dequeue+0x34e/0x8c0 net/sched/sch_sfq.c:493
sfq_reset+0x17/0x60 net/sched/sch_sfq.c:518
qdisc_reset+0x12e/0x600 net/sched/sch_generic.c:1035
tbf_reset+0x41/0x110 net/sched/sch_tbf.c:339
qdisc_reset+0x12e/0x600 net/sched/sch_generic.c:1035
dev…
Source: NIST National Vulnerability Database NVD
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-2025-37752 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2025-37752" on the vendor's site.
CVE-2025-37752 (Linux kernel) — CWE-129 / CVSS v3 7.8
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.
A vulnerability (CWE-129) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
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
-
1Identify 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。
-
2Post-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
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2025-37752 linux-lts Fixed in: 6.1.140-r0
- Debian DEBIAN-CVE-2025-37752 linux Fixed in: 6.1.135-1
- Ubuntu UBUNTU-CVE-2025-37752 linux
References
- advisory github.com
- advisory nvd.nist.gov
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web lists.debian.org