CVE-2025-37992 | net_sched: Flush gso_skb list too during ->change()

In the Linux kernel, the following vulnerability has been resolved: net_sched: Flush gso_skb list too during ->change() Previously, when reducing a qdisc's limit via the ->change() operation, only the main skb queue was trimmed, potentially leaving packets in the gso_skb list. This could result in NULL pointer dereference when we only check sch->limit against sch->q.qlen. This patch introduces a new helper, qdisc_dequeue_internal(), which ensures both the gso_skb list and the main queue are properly flushed when trimming excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie) are updated to use this helper in their ->change() routines.

Published: 2025-05-26 Last update: 2025-12-16 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2025-37992 is rated Low Risk (24/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.16%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-37992

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.12% 0.16% +0.04%
2 2026-03-22 0.03% 0.12% +0.09%
3 2025-12-17 0.03%

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-37992

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 3.6 [email protected]

Weakness enumeration for CVE-2025-37992

OS Trackers for CVE-2025-37992

vendor priority summary link
debian not yet assigned CVE-2025-37992 not yet assigned priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6. https://security-tracker.debian.org/tracker/CVE-2025-37992
redhat medium https://access.redhat.com/security/cve/CVE-2025-37992
suse medium https://www.suse.com/security/cve/CVE-2025-37992/
ubuntu medium CVE-2025-37992 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, ignored 168, released 168, needed 44, not-affected 23, needs-triage 2, pending 1. https://ubuntu.com/security/CVE-2025-37992

Affected software / configurations for CVE-2025-37992

Vendor Product Version Raw CPE
linux linux_kernel >= 3.5, < 5.10.238 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.11, < 5.15.184 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.16, < 6.1.140 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.2, < 6.6.92 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.7, < 6.12.30 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13, < 6.14.8 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 6.15 cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:*
linux linux_kernel 6.15 cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:*
linux linux_kernel 6.15 cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:*
linux linux_kernel 6.15 cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:*
linux linux_kernel 6.15 cpe:2.3:o:linux:linux_kernel:6.15:rc5:*:*:*:*:*:*
linux linux_kernel 6.15 cpe:2.3:o:linux:linux_kernel:6.15:rc6:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References for CVE-2025-37992

cvelogic Threat Intelligence