CVE-2025-37890 — Use After Free in Linux
Severity
7.8HIGHNVD
OSV8.8OSV5.9OSV4.7
EPSS
0.1%
top 76.01%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedMay 16
Latest updateFeb 27
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…
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitability: 1.8 | Impact: 5.9
Affected Packages15 packages
Also affects: Debian Linux 11.0