CVE-2025-66564 (GCVE-0-2025-66564)

Vulnerability from cvelistv5 – Published: 2025-12-04 22:37 – Updated: 2025-12-05 14:55
VLAI
Title
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-12-05 14:55 UTC
CWE
  • CWE-405 - Asymmetric Resource Consumption (Amplification)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7668 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
sigstore timestamp-authority Affected: < 2.0.3
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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