CVE-2026-49835: Github.com/sigstore/timestamp authority/v2 Sigstore Timestamp Authority Has OOM Vulnerability
MODERATECVE-2026-49835 is a MODERATE (CVSS 5.9) sigstore timestamp authority has oom vulnerability (CWE-770: Allocation of Resources Without Limits or Throttling) affecting Github.com/sigstore/timestamp authority/v2 libraries in the Go ecosystem. The issue involves sigstore timestamp authority has oom due to unbounded metric label cardinality. Remediation is available by upgrading affected packages to version 2.1.0.
CVE-2026-49835 at a Glance
Security Impact
CVSS: 5.9
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H).
How to Fix CVE-2026-49835
To remediate this vulnerability, upgrade all affected Github.com/sigstore/timestamp authority/v2 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/sigstore/timestamp-authority/v2 to 2.1.0Upgrade github.com/sigstore/timestamp-authority to Latest secure releaseRun the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/sigstore/timestamp-authority/v2How to Check if You Are Affected
To determine whether your application is affected by CVE-2026-49835, inspect your project dependencies for Github.com/sigstore/timestamp authority/v2:
inspect dependencies for github.com/sigstore/timestamp-authority/v2Analyze the terminal output to locate any version of Github.com/sigstore/timestamp authority/v2 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.1.0), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-770: Allocation of Resources Without Limits or Throttling, where the product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated. In Github.com/sigstore/timestamp authority/v2, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-49835 Affected Github.com/sigstore/timestamp authority/v2 Versions
2 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/sigstore/timestamp-authority/v2
|
Go |
< 2.1.0
|
2.1.0
|
|
github.com/sigstore/timestamp-authority
|
Go |
≤ 1.2.9
|
|
References
Frequently Asked Questions
What is CVE-2026-49835?
Which Github.com/sigstore/timestamp authority/v2 versions are affected?
What version fixes CVE-2026-49835?
Is github.com/sigstore/timestamp-authority/v2 affected?
Is github.com/sigstore/timestamp-authority affected?
What is the CVSS score of CVE-2026-49835?
What CWE is associated with CVE-2026-49835?
How can I check Go dependencies for CVE-2026-49835?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-9c54-x2g4-v92j",
"modified" : "2026-06-30T18:40:39Z",
"published" : "2026-06-30T18:40:39Z",
"aliases" : [ "CVE-2026-49835" ],
"summary" : "Sigstore Timestamp Authority has OOM due to unbounded metric label cardinality",
"details" : "### Impact\n\nAn unauthenticated remote attacker can trigger unbounded memory growth on the timestamp authority server.\n\nThis vulnerability exists because the global `wrapMetrics` middleware records the raw HTTP request path (`r.URL.Path`) and raw HTTP request method (`r.Method`) as Prometheus labels for latency and request count metric vectors. Since this middleware runs before standard routing occurs, it executes for all incoming requests, including those for unmatched paths (yielding 404 responses) or arbitrary request methods. The Prometheus library registers a new, permanent time-series entry for every distinct label combination. An attacker can continuously issue requests containing random paths (e.g., `/api/v1/timestamp/<uuid>`) or random HTTP methods to exhaust system memory.\n\n### Patches\n\nThis issue has been patched by limiting the metric label values to a strict allowlist of expected paths (`/ping`, `/api/v1/timestamp`, `/api/v1/timestamp/certchain`) and expected HTTP methods (`GET`, `POST`, `HEAD`, `OPTIONS`). Unrecognized paths or methods are normalized to a static string (`\"unrecognized\"`).\n\nUsers should update to version `v2.0.7` or later.\n\n### Workarounds\n\n1. Block or drop incoming requests with invalid HTTP methods or unknown request paths at a reverse proxy or load balancer before they reach the timestamp authority server.\n2. Configure rate-limiting on the public interface to prevent remote attackers from issuing millions of unique requests in a short duration.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/sigstore/timestamp-authority/v2"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "2.1.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 2.0.6"
}
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/sigstore/timestamp-authority"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"last_affected" : "1.2.9"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/sigstore/timestamp-authority/security/advisories/GHSA-9c54-x2g4-v92j"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/sigstore/timestamp-authority"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-770" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2026-06-30T18:40:39Z",
"nvd_published_at" : null
}
}