CVE-2026-49835: V2 · Sigstore Timestamp Authority has OOM due to unbounded metric label cardinality
Affects github.com/sigstore/timestamp-authority/v2Source GCVE Database
Not known to be exploited · CVSS 5.9 Medium : upgrade to 2.1.0 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 54% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.1.0
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade github.com/sigstore/timestamp-authority/v2 to 2.1.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Gogithub.com/sigstore/timestamp-authority/v2 | Affected
| Fixed in
|
| Gogithub.com/sigstore/timestamp-authority | Affected
| Fixed in– |
Ubuntu 26.10golang-github-sigstore-timestamp-authoritypkg:deb/ubuntu/golang-github-sigstore-timestamp-authority?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSgolang-github-sigstore-timestamp-authoritypkg:deb/ubuntu/golang-github-sigstore-timestamp-authority?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in version v2.0.7 and later, which restricts Prometheus metric labels to a strict allowlist and normalizes unknown labels to prevent unbounded memory growth. Users should upgrade to v2.0.7 or later. As a workaround, blocking invalid requests at a proxy or applying rate limiting can mitigate the issue until the patch is applied.
Description
Sigstore Timestamp Authority is a service for issuing RFC 3161 timestamps. Prior to 2.1.0, the global wrapMetrics middleware records raw HTTP request path r.URL.Path and raw HTTP request method r.Method as Prometheus labels for latency and request count metric vectors before routing, allowing an unauthenticated remote attacker to issue requests with random paths such as /api/v1/timestamp/<uuid> or random HTTP methods and create unbounded permanent time-series entries that exhaust memory. This issue is fixed in version 2.1.0.
References
- github.com/sigstore/timestamp-authority/security/advisories/GHSA-9c54-x2g4-v92j (opens in a new tab)
- github.com/sigstore/timestamp-authority/commit/506ec57b6ac2ea1e4739322e47453469425b69b5 (opens in a new tab)
- github.com/sigstore/timestamp-authority/releases/tag/v2.1.0 (opens in a new tab)
- ubuntu.com/security/CVE-2026-49835 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-49835 (opens in a new tab)