Vulnerability in Linux

CVE-2025-21768

In the Linux kernel, the following vulnerability has been resolved: net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels Some lwtunnels have a dst cache for post-transformation dst. If the packet destination did not change we may end up recording a reference to the lwtunnel in its own cache, and the lwtunnel state will never be freed. Discovered by the ioam6.sh test, kmemleak was recently fixed to catch per-cpu memory leaks. I'm not sure if rpl and seg6 can actually hit this, but in principle I don't see why not.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.002 (9.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 9.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-21768: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

  • Linux — versions 6c8702c60b88651072460f3f4026c7dfe2521d12, 4.10, 0
  • Linux Kernel — versions 6.14

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-21768?
CVE-2025-21768 is a medium-severity vulnerability in Linux, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 5.5/10. Published 2025-02-27.
How severe is CVE-2025-21768?
Medium severity. CVSS v3 base score is 5.5 out of 10.