CVE-2026-45292 is a medium-severity (CVSS 5.3) CWE-770 vulnerability in io.opentelemetry:opentelemetry-api. A fix is available for io.opentelemetry:opentelemetry-api — see the affected versions and patch details below.
opentelemetry-java: Unbounded Memory Allocation in W3C Baggage Propagation
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-45292.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-45292 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
io.opentelemetry:opentelemetry-api☕io.opentelemetry:opentelemetry-extension-trace-propagatorsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Overview
A vulnerability affects the baggage propagation implementation in
opentelemetry-api and opentelemetry-extension-trace-propagators. Parsing oversized baggage
causes unbounded memory allocation and CPU consumption. Because baggage is automatically
re-injected into every outgoing request, the effect can fan out to downstream services that
never received the original malicious request.
Technical Details
W3CBaggagePropagatordid not enforce any limit on the total size or entry count of thebaggageheader. The parser iterated character-by-character through the entire value regardless of length.JaegerPropagatorandOtTracePropagatorhad the same gap in their respective baggage extraction paths.- The W3C Baggage specification recommends a maximum of 8,192 bytes and 180 entries; none of these limits were enforced.
Impact
The practical availability impact for most deployments is limited. Every major Java HTTP server enforces its own header size limit (Tomcat, Jetty, Netty, Vert.x, and gRPC-Java all default to 8 KiB), constraining what an external attacker can deliver before the application is reached. The risk is higher when transport-layer limits are absent — e.g., a compromised internal service communicating over a non-HTTP or custom transport.
Remediation
Update to version 1.62.0 or later (#8380). The fix enforces limits consistent with the W3C Baggage specification at the propagator level:
- Maximum total baggage size: 8,192 bytes across all
baggageheader values - Maximum number of entries: 64
Headers that would exceed either limit are dropped at the point the limit is reached; already-extracted valid entries are retained.
Workarounds
Ensure HTTP header size limits are configured at the server or gateway level. Most Java HTTP servers enforce an 8 KiB header limit by default, which mitigates external attack vectors independently of this fix.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.opentelemetry:opentelemetry-api | all versions | 1.62.0io.opentelemetry:opentelemetry-api:1.62.0 |
| ☕Maven | io.opentelemetry:opentelemetry-extension-trace-propagators | all versions | 1.62.0io.opentelemetry:opentelemetry-extension-trace-propagators:1.62.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.opentelemetry:opentelemetry-api, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update io.opentelemetry:opentelemetry-api to 1.62.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-45292 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-45292 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-45292. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This is an Important denial of service vulnerability in OpenTelemetry Java's baggage propagation, affecting Red Hat products that use OpenTelemetry for telemetry. A remote attacker can exploit this by sending excessively large baggage, leading to uncontrolled memory and CPU usage. The vulnerability's impact can extend…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Data Grid 8.6.2 | opentelemetry-extension-trace-propagators | RHSA-2026:41951 |
| Red Hat Migration Toolkit for Applications 8.2 | mta/mta-solution-server-rhel9:1784109883 | RHSA-2026:43038 |
| Red Hat Offline Knowledge Portal 1.2.13 | offline-knowledge-portal/rhokp-rhel9:1782239370 | RHSA-2026:28573 |
| Red Hat OpenShift AI 3.4 | rhoai/odh-kserve-agent-rhel9:1787105144 | RHSA-2026:60520 |
| Red Hat OpenShift Dev Spaces 3.29 | devspaces/openvsx-rhel9:1783007534 | RHSA-2026:36820 |
Frequently Asked Questions
Is CVE-2026-45292 in your dependencies?
O3 Security finds CVE-2026-45292 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.