{"id":"CVE-2026-50273","aliases":["GHSA-38wr-vpc7-2mp4"],"title":"dd-trace-dotnet: Improper parsing of W3C baggage headers may lead to DoS","summary":"dd-trace-dotnet: Improper parsing of W3C baggage headers may lead to DoS","severity":"high","cvss":7.5,"cwe":["CWE-400","CWE-770"],"vendor":"Datadog","product":"Datadog.Trace","ecosystem":"nuget","affected":["Datadog.Trace < 3.43.0","Datadog.Trace.OpenTracing < 3.43.0"],"patched":["Datadog.Trace 3.43.0","Datadog.Trace.OpenTracing 3.43.0"],"published":"2026-07-15","updated":"2026-07-15","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-38wr-vpc7-2mp4","references":[{"url":"https://github.com/DataDog/dd-trace-dotnet/security/advisories/GHSA-38wr-vpc7-2mp4"},{"url":"https://github.com/advisories/GHSA-38wr-vpc7-2mp4"}],"tags":["ghsa","nuget"],"ingestedAt":"2026-07-15T23:47:19.147Z","epss":0.00793,"epssPercentile":0.5483,"slug":"CVE-2026-50273","body":"## Overview\n\n### Impact\nDatadog tracing libraries that implement W3C baggage propagation parse incoming baggage HTTP headers without enforcing item-count or byte-size limits on the extract path. The DD_TRACE_BAGGAGE_MAX_ITEMS (default 64) and DD_TRACE_BAGGAGE_MAX_BYTES (default 8192) limits were applied only to baggage injection, not extraction. A remote, unauthenticated attacker can send a request whose baggage header contains an arbitrarily large number of comma-separated key-value pairs (or a single very large value). The tracer allocates a hash-map entry for each pair on every request, causing unbounded CPU and memory consumption and enabling a remote Denial of Service against any HTTP service that has the baggage propagation style enabled.\nThe baggage propagation style is enabled by default in most affected tracers, so any internet-facing service that has been instrumented with an affected tracer version is exposed unless the propagation style has been explicitly narrowed.\n\n\n### Patches\nThis is resolved in version 3.43.0 and later of the `dd-trace-dotnet` library.\n\n### Workarounds\nIf users cannot upgrade immediately:\n1. Disable `baggage` extraction by removing `baggage` from `DD_TRACE_PROPAGATION_STYLE` (or `DD_TRACE_PROPAGATION_STYLE_EXTRACT` if set independently).\n2. Cap the maximum HTTP request header size at an upstream proxy or web server (for example, Apache `LimitRequestFieldSize`, Nginx `large_client_header_buffers`, Envoy `max_request_headers_kb`).\n\n### Resources\nRelated upstream advisories:\n[opentelemetry-go GHSA-mh2q-q3fh-2475](https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-mh2q-q3fh-2475)\n[opentelemetry-dotnet GHSA-g94r-2vxg-569j](https://github.com/open-telemetry/opentelemetry-dotnet/security/advisories/GHSA-g94r-2vxg-569j)\n\n## Affected packages\n\n- `Datadog.Trace < 3.43.0`\n- `Datadog.Trace.OpenTracing < 3.43.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `Datadog.Trace 3.43.0`\n- `Datadog.Trace.OpenTracing 3.43.0`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}