DEBIAN-CVE-2025-37890

Advisory lineage Upstream: 1 Downstream: 3
Upstream
CVE-2025-37890
Published: 16 May 2025, 13:15
Last modified:28 Apr 2026, 20:29

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

16 May 2025, 13:15
Published
Vulnerability first disclosed
28 Apr 2026, 20:29
Last Modified
Vulnerability information updated

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/

CVSS Metrics

  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • debian•linux

    < 5.10.244-1 | < 6.1.140-1 | < 6.12.29-1 | < 6.12.29-1

  • debian•linux-6.1

    < 6.1.140-1~deb11u1

References (1)