U.S. flag   An official website of the United States government
Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock (Dot gov) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

CVE-2025-37890 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc As described in Gerrard's report [1], we have a UAF case when an hfsc class has a netem child qdisc. The crux of the issue is that hfsc is assuming that checking for cl->qdisc->q.qlen == 0 guarantees that it hasn't inserted the class in the vttree or eltree (which is not true for the netem duplicate case). This patch checks the n_active class variable to make sure that the code won't insert the class in the vttree or eltree twice, catering for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to [email protected].

Hyperlink Resource
https://git.kernel.org/stable/c/141d34391abbb315d68556b7c67ad97885407547
https://git.kernel.org/stable/c/273bbcfa53541cde38b2003ad88a59b770306421
https://git.kernel.org/stable/c/2e7093c7a8aba5d4f8809f271488e5babe75e202
https://git.kernel.org/stable/c/6082a87af4c52f58150d40dec1716011d871ac21
https://git.kernel.org/stable/c/8df7d37d626430035b413b97cee18396b3450bef
https://git.kernel.org/stable/c/ac39fd4a757584d78ed062d4f6fd913f83bd98b5
https://git.kernel.org/stable/c/e0cf8ee23e1915431f262a7b2dee0c7a7d699af0
https://git.kernel.org/stable/c/e3e949a39a91d1f829a4890e7dfe9417ac72e4d0

Weakness Enumeration

CWE-ID CWE Name Source

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-37890
NVD Published Date:
05/16/2025
NVD Last Modified:
06/04/2025
Source:
kernel.org