GHSA-g94r-2vxg-569j
MEDIUMGHSA-g94r-2vxg-569j is a medium-severity (CVSS 5.3) vulnerability in OpenTelemetry.Api. O3 Security confirms whether GHSA-g94r-2vxg-569j is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
OpenTelemetry dotnet: Excessive memory allocation when parsing OpenTelemetry propagation headers
Blast Radius
OpenTelemetry.Api.NETOpenTelemetry.Extensions.PropagatorsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
Summary
The implementation details of the baggage, B3 and Jaeger processing code in the OpenTelemetry.Api and OpenTelemetry.Extensions.Propagators NuGet packages can allocate excessive memory when parsing which could create a potential denial of service (DoS) in the consuming application.
Details
Exceeding Limits
BaggagePropagator.Inject<T>() does not enforce the length limit of 8192 characters if the injected baggage contains only one item.
This change was introduced by #1048.
Excessive allocation
The following methods eagerly allocate intermediate arrays before applying size limits.
BaggagePropagator.Extract<T>()- this change was introduced by #1048.BaggagePropagator.Inject<T>()- this change was introduced by #1048.B3Propagator.Extract<T>()- this change was introduced by #533.B3Propagator.Extract<T>()- this change was introduced by #3244.JaegerPropagator.Extract<T>()- this change was introduced by #3309.
Impact
Excessively large propagation headers, particularly in degenerate/malformed cases that consist or large numbers of delimiter characters, can allocate excessive amounts of memory for intermediate storage of parsed content relative to the size of the original input.
Mitigation
HTTP servers often set maximum limits on the length of HTTP request headers, such as Internet Information Services (IIS) which sets a default limit of 16KB and nginx which sets a default limit of 8KB.
Workarounds
Possible workarounds include:
- Configuring appropriate HTTP request header limits.
- Disabling baggage and/or trace propagation.
Remediation
#7061 refactors the handling of baggage, B3 and Jaeger propagation headers to stop parsing eagerly when limits are exceeded and avoid allocating intermediate arrays.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | OpenTelemetry.Api | ≥ 0.5.0-beta.2&&< 1.15.3 | 1.15.3 |
| .NETNuGet | OpenTelemetry.Extensions.Propagators | ≥ 1.3.1&&< 1.15.3 | 1.15.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for OpenTelemetry.Api. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update OpenTelemetry.Api to 1.15.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-g94r-2vxg-569j 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 pinpoints whether GHSA-g94r-2vxg-569j is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-g94r-2vxg-569j. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-g94r-2vxg-569j in your dependencies?
O3 detects GHSA-g94r-2vxg-569j across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.