What is CVE-2023-43810?

CVE-2023-43810 is a high-severity uncontrolled resource consumption vulnerability in opentelemetry-instrumentation (pip), affecting versions < 0.41b0. It is fixed in 0.41b0. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.

How severe is CVE-2023-43810?

CVE-2023-43810 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.

Which versions of opentelemetry-instrumentation are affected by CVE-2023-43810?

opentelemetry-instrumentation (pip) versions < 0.41b0 is affected.

Is there a fix for CVE-2023-43810?

Yes. CVE-2023-43810 is fixed in 0.41b0. Upgrade to this version or later.

Is CVE-2023-43810 exploitable, and should I be worried?

Whether CVE-2023-43810 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.

What actually determines whether CVE-2023-43810 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.

CVE-2023-43810 in opentelemetry-instrumentation

Q: How severe is CVE-2023-43810?

CVE-2023-43810 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.

Q: Which versions of opentelemetry-instrumentation are affected by CVE-2023-43810?

opentelemetry-instrumentation (pip) versions < 0.41b0 is affected.

Q: Is there a fix for CVE-2023-43810?

Yes. CVE-2023-43810 is fixed in 0.41b0. Upgrade to this version or later.

Q: Is CVE-2023-43810 exploitable, and should I be worried?

Whether CVE-2023-43810 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.

Q: What actually determines whether CVE-2023-43810 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.

Q: How do I fix CVE-2023-43810?

Upgrade opentelemetry-instrumentation to 0.41b0 or later.

Summary

opentelemetry-instrumentation Denial of Service vulnerability due to unbound cardinality metrics

Autoinstrumentation out of the box adds the label http_method that has unbound cardinality. It leads to the server's potential memory exhaustion when many malicious requests are sent.

Details

HTTP method for requests can be easily set by an attacker to be random and long.

PoC

Send many requests with long randomly generated HTTP methods and observe how memory consumption increases during it. The app can be like this example from the official docs.

Proposed solution

For convenience and safe usage of this library, it should by default mark with the label UNKNOWN non-standard HTTP methods to show that such requests were made (and this way does not increase cardinality). In case someone wants to stay with the current behavior, library API should allow it. The mechanism with environment variables can be reused - introduce the variable OTEL_INSTRUMENTATION_HTTP_CAPTURE_ALL_METHODS that will allow enabling current behavior when someone really wants it.

Impact

In order to be affected program has to be instrumented for HTTP handlers and does not filter any unknown HTTP methods on the level of CDN, LB, previous middleware, etc.

Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.

CVE-2023-43810 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 (0.41b0); upgrading removes the vulnerable code path.

Affected versions

opentelemetry-instrumentation (< 0.41b0)

Security releases

opentelemetry-instrumentation → 0.41b0 (pip)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

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. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

Already deployed Kodem?

See it in your environment New to Kodem? Get a demo →

Remediation advice

Upgrade opentelemetry-instrumentation to 0.41b0 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2023-43810? CVE-2023-43810 is a high-severity uncontrolled resource consumption vulnerability in opentelemetry-instrumentation (pip), affecting versions < 0.41b0. It is fixed in 0.41b0. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.
How severe is CVE-2023-43810? CVE-2023-43810 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.
Which versions of opentelemetry-instrumentation are affected by CVE-2023-43810? opentelemetry-instrumentation (pip) versions < 0.41b0 is affected.
Is there a fix for CVE-2023-43810? Yes. CVE-2023-43810 is fixed in 0.41b0. Upgrade to this version or later.
Is CVE-2023-43810 exploitable, and should I be worried? Whether CVE-2023-43810 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
What actually determines whether CVE-2023-43810 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.
How do I fix CVE-2023-43810? Upgrade opentelemetry-instrumentation to 0.41b0 or later.