Sigstore Timestamp Authority allocates excessive memory during request parsing

Summary

Sigstore Timestamp Authority is a service for issuing RFC 3161 timestamps. Prior to 2.0.3, Function api.ParseJSONRequest currently splits (via a call to strings.Split) an optionally-provided OID (which is untrusted data) on periods. Similarly, function api.getContentType splits the Content-Type header (which is also untrusted data) on an application string. As a result, in the face of a malicious request with either an excessively long OID in the payload containing many period characters or a malformed Content-Type header, a call to api.ParseJSONRequest or api.getContentType incurs allocations of O(n) bytes (where n stands for the length of the function's argument). This vulnerability is fixed in 2.0.3.

Timeline

1. Dec 4, 2025, 10:37 PM UTCCVE published
2. Dec 5, 2025, 2:55 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: partial

3. Dec 5, 2025, 2:55 PM UTCRecord last updated

Affected versions

• sigstore timestamp-authority

  fixed in 2.0.3

• github.com/sigstore/timestamp-authorityGo

  fixed in 2.0.3

• github.com/sigstore/timestamp-authorityGo

  All versions

• github.com/sigstore/timestamp-authority/v2Go

  fixed in 2.0.3

References 2