CVE-2026-23831

Rekor COSE v0.0.1 Canonicalize crashes when passed empty Message

Published Jan 22, 2026 CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-273p-m2cw-6833 Rekor's COSE v0.0.1 entry type nil pointer dereference in Canonicalize via empty Message
History
Type Values Removed Values Added
First Time appeared Linuxfoundation
Linuxfoundation rekor
CPEs cpe:2.3:a:linuxfoundation:rekor:*:*:*:*:*:*:*:*
Vendors & Products Linuxfoundation
Linuxfoundation rekor
Type Values Removed Values Added
First Time appeared Sigstore
Sigstore rekor
Vendors & Products Sigstore
Sigstore rekor
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Rekor COSE v0.0.1 Canonicalize crashes when passed empty Message
Weaknesses CWE-476
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jan 23, 2026, 2:32 PM
Reserved
Jan 16, 2026, 3:46 PM
Status
Analyzed
Published
Jan 22, 2026, 10:16 PM
Modified
Jun 17, 2026, 10:22 AM
Severity
Moderate
Public date
Jan 22, 2026, 9:26 PM