{"cve":"CVE-2026-114603","nvd":{"published":"2026-10-22T16:17:34.860","modified":"2026-10-22T17:29:28.470","status":"Awaiting Analysis","description":"OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.1, the opentelemetry-api function TraceState.from_header in opentelemetry/trace/span.py, reached through TraceContextTextMapPropagator.extract, parses inbound W3C tracestate headers with an unbounded optional-whitespace regular expression. A malformed header containing a long run of spaces or tabs without a following comma causes quadratic backtracking before the member-count limit is applied. Services using the default W3C Trace Context propagator can therefore spend excessive CPU time on one unauthenticated request when the HTTP server, parser, gateway, or custom carrier accepts a sufficiently large header. The processing can occupy a synchronous worker or delay unrelated requests on the same asynchronous event loop. The impact is limited to availability and does not expose or modify telemetry data or allow code execution. This issue is fixed in version 1.45.1.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","score":5.3},"cwes":["CWE-400","CWE-1333"],"references":["https://github.com/open-telemetry/opentelemetry-python/blob/main/CHANGELOG.md#version-1451066b1-2026-10-06","https://github.com/open-telemetry/opentelemetry-python/commit/d5224bf4ffdf2aee1b592ad238dcc32ca957f26b","https://github.com/open-telemetry/opentelemetry-python/pull/5749","https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.45.1","https://github.com/open-telemetry/opentelemetry-python/security/advisories/GHSA-xcq7-p3pf-p88h"],"products":[],"source":"nvd","synced_at":"2026-10-23T16:39:28.036610720+00:00"},"epss":{"cve":"CVE-2026-114603","score":0.00487,"percentile":0.41639,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-xcq7-p3pf-p88h","url":"https://osv.dev/vulnerability/GHSA-xcq7-p3pf-p88h","summary":"OpenTelemetry Python: Unbounded tracestate parsing in opentelemetry-api","modified":"2026-10-22T16:30:40.999595074Z","packages":[{"ecosystem":"PyPI","name":"opentelemetry-api","purl":"pkg:pypi/opentelemetry-api","ranges":["<1.45.1"],"fixed":["1.45.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}