# CVE-2023-45142: OpenTelemetry-Go Contrib has DoS vulnerability in otelhttp due to unbound cardinality metrics > Attackers can cause memory exhaustion and denial of service by sending requests with unbounded User-Agent or HTTP method values to applications using the otelhttp handler. - **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 12 Oct 2023 - **Updated:** 13 Feb 2025 - **Also known as:** AZL-31303, AZL-33347, AZL-33516, AZL-34580, AZL-34889, AZL-34900, AZL-35069, AZL-35116, AZL-35119, AZL-35437, AZL-39972, CLEANSTART-2026-LO55255, CLEANSTART-2026-WY63823, GHSA-rcjv-mgp8-qvmr, GO-2023-2113, MINI-3r5c-gj59-qq3m, MINI-5p26-qmxg-8743, MINI-6wpv-j2c4-g55m, MINI-ffvg-hhxx-mf77, MINI-g7fh-v9h2-x522, MINI-j2rf-hq9p-q8rq, MINI-pq7v-2926-5jch, MINI-px4f-gj5c-p9wj, UBUNTU-CVE-2023-45142, openSUSE-SU-2024:13495-1, openSUSE-SU-2024:14232-1 ## What is CVE-2023-45142? CVE-2023-45142 is a high-severity denial of service vulnerability in open-telemetry opentelemetry-go-contrib, published on 12 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description OpenTelemetry-Go Contrib is a collection of third-party packages for OpenTelemetry-Go. A handler wrapper out of the box adds labels `http.user_agent` and `http.method` that have unbound cardinality. It leads to the server's potential memory exhaustion when many malicious requests are sent to it. HTTP header User-Agent or HTTP method for requests can be easily set by an attacker to be random and long. The library internally uses `httpconv.ServerRequest` that records every value for HTTP `method` and `User-Agent`. In order to be affected, a program has to use the `otelhttp.NewHandler` wrapper and not filter any unknown HTTP methods or User agents on the level of CDN, LB, previous middleware, etc. Version 0.44.0 fixed this issue when the values collected for attribute `http.request.method` were changed to be restricted to a set of well-known values and other high cardinality attributes were removed. As a workaround to stop being affected, `otelhttp.WithFilter()` can be used, but it requires manual careful configuration to not log certain requests entirely. For convenience and safe usage of this library, it should by default mark with the label `unknown` non-standard HTTP methods and User agents to show that such requests were made but do not increase cardinality. In case someone wants to stay with the current behavior, library API should allow to enable it. Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling) ## Which versions are affected by CVE-2023-45142? 21 open source packages ship an affected version, including go.opentelemetry.io/contrib/instrumentation/github.com/emicklei/go-restful/otelrestful, go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin and go.opentelemetry.io/contrib/instrumentation/github.com/gorilla/mux/otelmux. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `go.opentelemetry.io/contrib/instrumentation/github.com/emicklei/go-restful/otelrestful` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/emicklei/go-restful/otelrestful` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/emicklei/go-restful/otelrestful` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/gorilla/mux/otelmux` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/gorilla/mux/otelmux` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/gorilla/mux/otelmux` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/labstack/echo/otelecho` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/labstack/echo/otelecho` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/github.com/labstack/echo/otelecho` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/gopkg.in/macaron.v1/otelmacaron` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/gopkg.in/macaron.v1/otelmacaron` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/gopkg.in/macaron.v1/otelmacaron` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/net/http/httptrace/otelhttptrace` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/net/http/httptrace/otelhttptrace` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/net/http/httptrace/otelhttptrace` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp` | Go | All versions | 0.44.0 | | `go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp` | Go | All versions | 0.44.0 | | `caddy` | openSUSE:Tumbleweed | All versions | 2.7.6-1.1 | | `golang-github-prometheus-prometheus` | openSUSE:Tumbleweed | All versions | 2.53.0-3.1 | Products: Opentelemetry Opentelemetry. ## How do I fix CVE-2023-45142? Upgrade go.opentelemetry.io/contrib/instrumentation/github.com/emicklei/go-restful/otelrestful to 0.44.0 or later. ## Is CVE-2023-45142 being exploited? There is no known exploitation of CVE-2023-45142 in the wild and no public exploit code. ## Other vulnerabilities in open-telemetry opentelemetry-go-contrib - [CVE-2026-29181](https://insights.sbomify.com/CVE-2026-29181/): OpenTelemetry-Go multi-value `baggage` header extraction causes excessive allocations (remote dos amplification) (high 7.5) - [CVE-2023-47108](https://insights.sbomify.com/CVE-2023-47108/): DoS vulnerability in otelgrpc (uncontrolled resource consumption) due to unbound cardinality metrics (high 7.5) - [CVE-2023-43810](https://insights.sbomify.com/CVE-2023-43810/): opentelemetry-instrumentation Denial of Service vulnerability due to unbound cardinality metrics (high 7.5) - [CVE-2026-39883](https://insights.sbomify.com/CVE-2026-39883/): opentelemetry-go: BSD kenv command not using absolute path enables PATH hijacking (high 7.3) - [CVE-2026-24051](https://insights.sbomify.com/CVE-2026-24051/): OpenTelemetry-Go Affected by Arbitrary Code Execution via PATH Hijacking (high 7.0) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-45142 and fix it if it is affected. What it is: CVE-2023-45142 is a high-severity denial of service vulnerability in open-telemetry opentelemetry-go-contrib, published on 12 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2023-45142 in the wild and no public exploit code. Affected packages and fixed versions: - go.opentelemetry.io/contrib/instrumentation/github.com/emicklei/go-restful/otelrestful (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/emicklei/go-restful/otelrestful (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/emicklei/go-restful/otelrestful (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/gorilla/mux/otelmux (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/gorilla/mux/otelmux (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/gorilla/mux/otelmux (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/labstack/echo/otelecho (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/labstack/echo/otelecho (Go): affected all versions; fixed in 0.44.0 - go.opentelemetry.io/contrib/instrumentation/github.com/labstack/echo/otelecho (Go): affected all versions; fixed in 0.44.0 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2023-45142/ (Markdown: https://insights.sbomify.com/CVE-2023-45142/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-45142 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-45142 - OSV: https://osv.dev/vulnerability/CVE-2023-45142 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-45142/ Summaries are generated and may contain mistakes; the official description above is the record.