Vulnerability in Linux

CVE-2025-40240

In the Linux kernel, the following vulnerability has been resolved: sctp: avoid NULL dereference when chunk data buffer is missing chunk->skb pointer is dereferenced in the if-block where it's supposed to be NULL only. chunk->skb can only be NULL if chunk->head_skb is not. Check for frag_list instead and do it just before replacing chunk->skb. We're sure that otherwise chunk->skb is non-NULL because of outer if() condition.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.006 (46.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 46.9% 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-2025-40240: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

  • Linux — versions 90017accff61ae89283ad9a51f9ac46ca01633fb, 4.8, 0

References

Frequently asked questions

What is CVE-2025-40240?
CVE-2025-40240 is a high-severity vulnerability in Linux. CVSS score: 7.5/10. Published 2025-12-04.
How severe is CVE-2025-40240?
High severity. CVSS v3 base score is 7.5 out of 10.