CVE-2026-23886
Swift W3C TraceContext vulnerable to a malformed HTTP header causing a crash
Impact
### Impact A denial-of-service vulnerability due to improper input validation allows a remote attacker to crash the service via a malformed HTTP header. Allows crashing the process with data coming from the network when used with, for example, an HTTP server. Most common way of using Swift W3C Trace Context is through Swift OTel. ### Patches https://github.com/swift-otel/swift-w3c-trace-context/commit/5da9b143ba6046734de3fa51dafea28290174e4e ### Workarounds Disable either Swift OTel or the code that extracts the trace information from an incoming header (such as a `TracingMiddleware`). ### References [Swift W3C TraceContext 1.0.0-beta.5](https://github.com/swift-otel/swift-w3c-trace-context/releases/tag/1.0.0-beta.5) [Swift OTel 1.0.4](https://github.com/swift-otel/swift-otel/releases/tag/1.0.4)
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| swift | github.com/swift-otel/swift-w3c-trace-context | < 1.0.0-beta.5 | 1.0.0-beta.5 |
| swift | github.com/swift-otel/swift-otel | < 1.0.4 | 1.0.4 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/swift-otel/swift-otel/releases/tag/1.0.4
- https://github.com/swift-otel/swift-w3c-trace-context/commit/5da9b143ba6046734de3fa51dafea28290174e4e
- https://github.com/swift-otel/swift-w3c-trace-context/releases/tag/1.0.0-beta.5
- https://github.com/swift-otel/swift-w3c-trace-context/security/advisories/GHSA-mvpq-2v8x-ww6g
- https://github.com/advisories/GHSA-mvpq-2v8x-ww6g
- https://nvd.nist.gov/vuln/detail/CVE-2026-23886