GHSA-8785-wc3w-h8q6
OpenTelemetry .NET has Denial of Service (DoS) Vulnerability in API Package
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| NuGet | OpenTelemetry.Api | >= 1.11.0, < 1.11.2 | 1.11.2 |
| NuGet | OpenTelemetry.Api | 1.10.0 | no fix listed |
| NuGet | OpenTelemetry.Api | 1.10.0-beta.1 | no fix listed |
| NuGet | OpenTelemetry.Api | 1.10.0-rc.1 | no fix listed |
| NuGet | OpenTelemetry.Api | 1.11.0-rc.1 | no fix listed |
Details
As written in the advisory (Markdown source, shown as plain text).
### Impact
_What kind of vulnerability is it? Who is impacted?_
A vulnerability in `OpenTelemetry.Api` package `1.10.0` to `1.11.1` could cause a Denial of Service (DoS) when a `tracestate` and `traceparent` header is received.
* Even if an application does not explicitly use trace context propagation, receiving these headers can still trigger high CPU usage.
* This issue impacts any application accessible over the web or backend services that process HTTP requests containing a `tracestate` header.
* Application may experience excessive resource consumption, leading to increased latency, degraded performance, or downtime.
### Patches
_Has the problem been patched? What versions should users upgrade to?_
This issue has been <strong data-start="1143" data-end="1184">resolved in OpenTelemetry.Api 1.11.2</strong> by <strong data-start="1188" data-end="1212">reverting the change</strong> that introduced the problematic behavior in versions <strong data-start="1266" data-end="1286">1.10.0 to 1.11.1</strong>.</li><li data-start="1290" data-end="1409">The fix ensures that <strong data-start="1313" data-end="1380">valid tracing headers no longer cause excessive CPU consumption</strong> when received in requests.</li></ul><h4 data-start="1411" data-end="1434"><strong data-start="1416" data-end="1434">Fixed Version:</strong></h4>
OpenTelemetry .NET Version | Status
-- | --
<= 1.9.x | ✅ Not affected
1.10.0 - 1.11.1 | ❌ Vulnerable
1.11.2 (Fixed) | ✅ Safe to use
**Upgrade Command:**
```
dotnet add package OpenTelemetry --version 1.11.2
```
**Delisting of Affected Packages**
To prevent accidental usage, we have delisted the affected versions (1.10.0 to 1.11.1) from NuGet. Users should avoid these versions and upgrade to 1.11.2 immediately.
### Workarounds
_Is there a way for users to fix or remediate the vulnerability without upgrading?_
### References
_Are there any links users can visit to find out more?_
References
External links from the advisory. They lead to third-party sites.
- https://github.com/open-telemetry/opentelemetry-dotnet/security/advisories/GHSA-8785-wc3w-h8q6
- https://nvd.nist.gov/vuln/detail/CVE-2025-27513
- https://github.com/open-telemetry/opentelemetry-dotnet/pull/6161
- https://github.com/open-telemetry/opentelemetry-dotnet/commit/1b555c1201413f2f55f2cd3c4ba03ef4b615b6b5
- https://github.com/open-telemetry/opentelemetry-dotnet