CVE-2026-54788

datadog-opentelemetry has unbounded W3C tracestate parsing that may lead to DoS

Workarounds

If you cannot upgrade immediately:

1. Disable tracecontext extraction by setting DD_TRACE_PROPAGATION_STYLE_EXTRACT to a value that does not include tracecontext (for example, datadog).
2. Cap the maximum HTTP request header size at an upstream proxy or web server.

Datadog tracing libraries that implement W3C Trace Context (tracecontext) propagation parse the incoming tracestate header without enforcing a size cap on the Datadog vendor entry (dd=...). The dd= value contains semicolon-separated key:value pairs, and the parser allocates a hash-map entry for each pair. A remote, unauthenticated attacker can send a tracestate header whose dd= member is arbitrarily large (or contains an arbitrarily large number of pairs), forcing unbounded CPU and memory consumption per request and enabling a remote Denial of Service. tracecontext extraction is enabled by default in affected tracers, so any internet-facing service instrumented with an affected version is exposed unless tracecontext has been explicitly removed from the propagation style configuration.

The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap. Typical impact: resource exhaustion leading to denial of service.

CVE-2026-54788 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.3.3); upgrading removes the vulnerable code path.

Kodem intelligence

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This is resolved in version 0.3.3 and later of the dd-trace-rs library.

1. What is CVE-2026-54788? CVE-2026-54788 is a high-severity allocation of resources without limits or throttling vulnerability in datadog-opentelemetry (rust), affecting versions >= 0.1.0, < 0.3.3. It is fixed in 0.3.3. The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap.
2. How severe is CVE-2026-54788? CVE-2026-54788 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of datadog-opentelemetry are affected by CVE-2026-54788? datadog-opentelemetry (rust) versions >= 0.1.0, < 0.3.3 is affected.
4. Is there a fix for CVE-2026-54788? Yes. CVE-2026-54788 is fixed in 0.3.3. Upgrade to this version or later.
5. Is CVE-2026-54788 exploitable, and should I be worried? Whether CVE-2026-54788 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-54788 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-54788? Upgrade datadog-opentelemetry to 0.3.3 or later.