7.5

CVE-2025-40240: sctp: avoid NULL dereference when chunk data buffer is missing

Deferred
AliasesRHSA-2026:4899UBUNTU-CVE-2025-40240DEBIAN-CVE-2025-40240
Published 04-12-2025Last modified 05-08-2026

Vulnerability summary

CVE-2025-40240 is a high (CVSS 7.5) vulnerability in linux. EPSS estimates a 0.60% chance of exploitation in the next 30 days, higher than 48.7% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.60%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 59 · Related 42
DLA-4404-1OPENSUSE-SU-2026:20145-1RHSA-2026:0443RHSA-2026:0444RHSA-2026:0445RHSA-2026:0453

Timeline

  1. 04-12-2025
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.60%

Chance of exploitation in the next 30 days

Percentile

49%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.60% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu152 products
  • linuxAll versions (No fix recorded) | < 5.15.0-170.180 | < 6.8.0-106.106 | < 6.17.0-14.14
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1100.107 | < 6.8.0-1050.53 | < 6.17.0-1007.7
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Redhat46 products
  • bpftool< 0:7.3.0-427.115.1.el9_4
  • bpftool-debuginfo< 0:7.3.0-427.115.1.el9_4
  • kernel< 0:5.14.0-427.115.1.el9_4
  • kernel-64k< 0:5.14.0-427.115.1.el9_4
  • kernel-64k-core< 0:5.14.0-427.115.1.el9_4
Debian1 product
  • linux< 6.1.158-1 | < 6.12.57-1 | < 6.17.6-1
Linux1 product
  • linux≥ 90017accff61ae89283ad9a51f9ac46ca01633fb, < 61cda2777b07d27459f5cac5a047c3edf9c8a1a9 | ≥ 90017accff61ae89283ad9a51f9ac46ca01633fb, < 08165c296597075763130919f2aae59b5822f016 | ≥ 90017accff61ae89283ad9a51f9ac46ca01633fb, < 03e80a4b04ef1fb2c61dd63216ab8d3a5dcb196f | ≥ 90017accff61ae89283ad9a51f9ac46ca01633fb, < 4f6da435fb5d8a21cbf8cae5ca5a2ba0e1012b71 | ≥ 90017accff61ae89283ad9a51f9ac46ca01633fb, < cb9055ba30306ede4ad920002233d0659982f1cb | ≥ 90017accff61ae89283ad9a51f9ac46ca01633fb, < 7a832b0f99be19df608cb75c023f8027b1789bd1 | ≥ 90017accff61ae89283ad9a51f9ac46ca01633fb, < 89b465b54227c245ddc7cc9ed822231af21123ef | ≥ 90017accff61ae89283ad9a51f9ac46ca01633fb, < 441f0647f7673e0e64d4910ef61a5fb8f16bfb82 | 4.8

4 vendors · 200 products · Showing 200 of 232

References

48 links
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