Medium 5.3Published Jan 22, 2026

CVE-2026-23831Rekor COSE v0.0.1 Canonicalize crashes when passed empty Message

Updated under an hour ago (Oct 27, 2026, 7:30 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for sigstore rekor

Exploited in the last 30 days

Rekor is a software supply chain transparency log. In versions 1.4.3 and below, the entry implementation can panic on attacker-controlled input when canonicalizing a proposed entry with an empty spec.message, causing nil Pointer Dereference. Function validate() returns nil (success) when message is empty, leaving sign1Msg uninitialized, and Canonicalize() later dereferences v.sign1Msg.Payload. A malformed proposed entry of the cose/v0.0.1 type can cause a panic on a thread within the Rekor process. The thread is recovered so the client receives a 500 error message and service still continues, so the availability impact of this is minimal. This issue has been fixed in version 1.5.0.

CVSS: 5.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness (CWE): CWE-476
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jan 23, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

sigstore rekor sigstore:rekor (from the name)	before 1.5.0	CNA record
linuxfoundation rekor linuxfoundation:rekor	before 1.5.0	NVD

References

References

https://github.com/sigstore/rekor/security/advisories/GHSA-273p-m2cw-6833	x-refsource-confirm, vendor-advisory
https://github.com/sigstore/rekor/commit/39bae3d192bce48ef4ef2cbd1788fb5770fee8cd	x-refsource-misc, patch
https://github.com/sigstore/rekor/releases/tag/v1.5.0	x-refsource-misc, product, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.