Double Free in Linux

CVE-2025-37914

In the Linux kernel, the following vulnerability has been resolved: net_sched: ets: Fix double list add in class with netem as child qdisc As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of ets, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. In addition to checking for qlen being zero, this patch checks whether the class was already added to the active_list (cl_is_active) before doing the addition to cater for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

Vulnerability class: Double Free

EPSS: 0.002 (7.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-37914?
CVE-2025-37914 is a high-severity vulnerability in Linux, classified under Double Free. CVSS score: 7.8/10. Published 2025-05-20.
How severe is CVE-2025-37914?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2025-37914 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.