opentelemetry-java: Quadratic CPU consumption in W3C tracestate parsing
CVE-2026-118259
Summary OpenTelemetry Java's W3C trace-context propagator permits excessive CPU consumption when extracting crafted tracestate headers, potentially leading to denial of service. Regex backtracking causes quadratic parsing time for headers containing long runs of spaces or tabs without a following comma. Impact An unauthenticated attacker whose headers reach W3CTraceContextPropagator.extract() can cause excessive CPU usage through crafted requests. Parsing blocks the calling thread, potentially affecting other connections when extraction runs on a shared event-loop thread. Actual impact depends on ingress header-size limits, proxy configuration, and threading. Header-size limits reduce the per-request cost but do not eliminate the vulnerability. Patches Upgrade io.opentelemetry:opentelemetry-api to version 1.67.0 or later. [PR #8914](https://github.com/open-telemetry/opentelemetry-java/pull/8914) replaces regex delimiter splitting with literal comma scanning and explicit whitespace trimming. Workarounds If upgrading is not possible, reject or remove oversized tracestate headers before trace-context extraction. This reduces the per-request parsing cost but does not eliminate the…
Assessment
- CVSS
- 5.3 (v3.1)
- Severity
- Medium
- EPSS
- 0.0049% chance of exploitation in the next 30 days
- Known exploited
- Not listed in CISA KEV
- Exploit availability
- Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
- Published
- 28 October 2026
- Last updated
- 28 October 2026
- Affected
- maven · io.opentelemetry:opentelemetry-api
- Weakness
- CWE-1333
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
At the source
References
- https://github.com/open-telemetry/opentelemetry-java/security/advisories/GHSA-ccrj-gw8r-854m
- https://github.com/open-telemetry/opentelemetry-java/pull/8914
- https://github.com/open-telemetry/opentelemetry-java/commit/ba4dfea91647d1ef596975db5d7197681df3c0f5
- https://github.com/open-telemetry/opentelemetry-java/commit/cc4f5f22aed0d69369941cde8029e73507cf438f
- https://github.com/open-telemetry/opentelemetry-java/releases/tag/v1.67.0
- https://github.com/advisories/GHSA-ccrj-gw8r-854m
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