CVE Feed
5.3 Medium

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

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