CVE-2026-72398: sctp: add INIT verification after cookie unpacking
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 0.7%
EPSS score, percentile 54.8 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 9.8 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 2.6.12
Unaffected before 2.6.12; 6.6.160; 6.12.114; 6.18.40; 7.1.5; 7.2
Source: CISA KEV 2026.10.29, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from 1da177e4c3f4 to before 81892d83cc89 |
| Affected | from 1da177e4c3f4 to before 683a012b984f |
| Affected | from 1da177e4c3f4 to before bca3100f5502 |
| Affected | from 1da177e4c3f4 to before 062bcbf8d1f1 |
| Affected | from 1da177e4c3f4 to before 414c5447fe6a |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 2.6.12 |
| Unaffected | before 2.6.12 |
| Unaffected | 6.6.160 |
| Unaffected | 6.12.114 |
| Unaffected | 6.18.40 |
| Unaffected | 7.1.5 |
| Unaffected | 7.2 |
Versions not listed are: affected.
Versions the record lists as unaffected: 6.6.160, 6.12.114, 6.18.40, 7.1.5, 7.2.
Source: CVE List, as of . About the data.
About this vulnerability
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 ena…
Summary: CVE record, as of .
- CISA has not added CVE-2026-72398 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
- The CVE record was published on 15 Aug 2026.
- The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.7% (percentile 54.8), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable yes, technical impact total.
Source: CISA KEV 2026.10.29, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
sctp: add INIT verification after cookie unpacking
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.
Source: CVE List, as of . About the data.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated |
Known exploited Linux vulnerabilities
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