9.8

CVE-2026-72398: linux

CVSS: 9.8v3.1CriticalReceived
AliasesUBUNTU-CVE-2026-72398DEBIAN-CVE-2026-72398
Published 15-08-2026Last modified 16-10-2026

Vulnerability summary

CVE-2026-72398 is a critical (CVSS 9.8) vulnerability in linux. EPSS estimates a 0.72% chance of exploitation in the next 30 days, higher than 53.1% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.72%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 21 · Related 21

Timeline

  1. 15-08-2026
    PublishedVulnerability first disclosed.
  2. 16-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: sctp: add INIT verification after cookie unpacking In SCTP handshake, the INIT chunk is initially processed by the server and embedded into the cookie carried in INIT-ACK. The client then returns this cookie via COOKIE-ECHO, where the server unpacks it and reconstructs the original INIT chunk. When cookie authentication is enabled, the cookie contents are protected against tampering, so reusing the unpacked INIT without re-verification is safe. However, when cookie authentication is disabled, the reconstructed INIT can no longer be trusted. In this case, the INIT must be explicitly validated after unpacking to avoid processing potentially tampered data. Add sctp_verify_init() checks after cookie unpacking in COOKIE-ECHO processing paths (sctp_sf_do_5_1D_ce() and sctp_sf_do_5_2_4_dupcook()) when cookie_auth_enable is disabled. On failure, the new association is freed and the packet is discarded. Also tighten cookie validation in sctp_unpack_cookie() by verifying the embedded chunk type is SCTP_CID_INIT before treating it as an INIT chunk. Finally, update sctp_verify_init() to validate parameter bounds using the actual embedded INIT length instead of chunk->chunk_end, since the INIT stored in COOKIE-ECHO may not span the entire chunk buffer.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.72%

Chance of exploitation in the next 30 days

Percentile

53%

Versus all other CVEs

30-day change

+0.02 pp

From 0.70% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.72%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu169 products
  • linuxAll versions (No fix recorded) | < 7.0.0-34.34
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 7.0.0-1013.13
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian1 product
  • linuxAll versions (No fix recorded) | < 7.1.5-1
Linux1 product
  • linux≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < bca3100f550281c2f2418652338bced3b35af0e6 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 062bcbf8d1f1051fdeb20b94920031b0e2cb95a2 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 414c5447fe6a200613dd46d7fdc8454622076cb1 | 2.6.12

3 vendors · 171 products

References

14 links
Show all 14 references