CVE-2025-66564
Description
A flaw was found in Sigstore Timestamp Authority. This vulnerability allows a denial of service via excessive memory allocation when processing a specially crafted Object Identifier or Content-Type header.
Statement
This vulnerability is rated Important for Red Hat products. The Sigstore Timestamp Authority, a service for issuing RFC 3161 timestamps, is prone to excessive memory allocation. This occurs when processing untrusted OID payloads with many period characters or malformed Content-Type headers. An unauthenticated attacker could exploit this flaw to trigger a denial of service in affected Red Hat products that utilize this component.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Amplification; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
Sometimes this is a factor in "flood" attacks, but other types of amplification exist.
Frequently Asked Questions
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