CVE-2026-23831: Rekor COSE v0.0.1 Canonicalize crashes when passed empty Message
Summary
Rekor’s cose v0.0.1 entry implementation can panic on attacker-controlled input when canonicalizing a proposed entry with an empty spec.message. validate() returns nil (success) when message is empty, leaving sign1Msg uninitialized, and Canonicalize() later dereferences v.sign1Msg.Payload.
Impact
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.
Patches
Upgrade to v1.5.0
Workarounds
None
Other sources
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.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-23831?
The severity of CVE-2026-23831 is categorized as critical due to the potential for attacker-controlled input causing application panic.
How do I fix CVE-2026-23831?
To fix CVE-2026-23831, update the Rekor package to version 1.5.0 or later.
What versions of Rekor are affected by CVE-2026-23831?
CVE-2026-23831 affects versions of Rekor up to and including 1.4.3.
What specific vulnerability does CVE-2026-23831 address?
CVE-2026-23831 addresses a panic issue in Rekor's cose v0.0.1 entry implementation with uninitialized sign1Msg when message is empty.
Is there a safe version of Rekor for use against CVE-2026-23831?
Yes, version 1.5.0 of Rekor is considered safe against CVE-2026-23831.