Medium 5.3Published Oct 22, 2026

CVE-2026-114603OpenTelemetry Python: Unbounded tracestate parsing in opentelemetry-api

Updated under an hour ago (Oct 28, 2026, 3:10 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for open-telemetry opentelemetry-python

Exploited in the last 30 days

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: 5.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness (CWE): CWE-400, CWE-1333
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Awaiting Analysis
Record last updated: Oct 22, 2026
First seen by InfoSec Signals: Oct 22, 2026

Affected products

Affected products

open-telemetry opentelemetry-python open_telemetry:opentelemetry_python (from the name)	before 1.45.1	CNA record

References

References

https://github.com/open-telemetry/opentelemetry-python/security/advisories/GHSA-xcq7-p3pf-p88h	x-refsource-confirm
https://github.com/open-telemetry/opentelemetry-python/pull/5749	x-refsource-misc
https://github.com/open-telemetry/opentelemetry-python/commit/d5224bf4ffdf2aee1b592ad238dcc32ca957f26b	x-refsource-misc
https://github.com/open-telemetry/opentelemetry-python/blob/main/CHANGELOG.md#version-1451066b1-2026-10-06	x-refsource-misc
https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.45.1	x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.