opentelemetry-java: Quadratic CPU consumption in W3C tracestate parsing

published 2026-10-28 11 d ago modified 2026-11-02 6 d ago also GHSA-ccrj-gw8r-854m , EUVD-2026-112368

cvss: 5.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 42%
public exploits: 0; none known

opentelemetry-java is the Java implementation of the OpenTelemetry API for recording telemetry, and SDK for managing telemetry recorded by the API. Prior to 1.67.0, W3CTraceContextPropagator.extract() uses regex delimiter processing that can exhibit quadratic backtracking while parsing tracestate headers containing long runs of spaces or tabs without a following comma. An unauthenticated attacker whose headers reach extraction can repeatedly block request or event-loop threads and cause excessive CPU consumption, with practical impact bounded by ingress header-size limits, proxy configuration, and threading. This issue is fixed in version 1.67.0.

Patch / fix

fixed in 1 links 4

maven io.opentelemetry:opentelemetry-api 1.67.0

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 6 d ago (2026-11-02)

Exploit prediction

0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
GitHub	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected packages

ecosystem	package	affected	fixed in
maven	io.opentelemetry:opentelemetry-api	<1.67.0	1.67.0

Affected products

open-telemetry opentelemetry-java

Classification

Weakness

CWE-1333 Inefficient Regular Expression Complexity

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary