Vulnerability-Lookup

GHSA-28XM-PRXC-5866

Vulnerability from github – Published: 2026-04-23 21:44 – Updated: 2026-04-23 21:44

Summary

OpenTelemetry.Sampler.AWS & OpenTelemetry.Resources.AWS have unbounded HTTP response body reads

Details

Summary

OpenTelemetry.Sampler.AWS reads unbounded HTTP response bodies from a configured AWS X-Ray remote sampling endpoint into memory.

OpenTelemetry.Resources.AWS reads unbounded HTTP response bodies from a configured AWS EC2/ECS/EKS remote instance metadata service endpoint into memory.

Both of these would allow an attacker-controlled endpoint or be acting as a Man-in-the-Middle (MitM) to cause excessive memory allocation and possible process termination (via Out of Memory (OOM)).

Details

OpenTelemetry.Sampler.AWS

AWSXRaySamplerClient.DoRequestAsync called HttpClient.SendAsync followed by ReadAsStringAsync(), which materializes the entire HTTP response body into a single in-memory string with no size limit. The sampling endpoint is configurable via AWSXRayRemoteSamplerBuilder.SetEndpoint (default: http://localhost:2000).

An attacker who controls the configured endpoint, or who can intercept traffic to it (MitM), can return an arbitrarily large response body. This causes unbounded heap allocation in the consuming process, leading to high transient memory pressure, garbage-collection stalls, or an OutOfMemoryException that terminates the process.

OpenTelemetry.Resources.AWS

The AWSEC2Detector, AWSECSDetector and AWSEKSDetector classes all make HTTP requests to the relevant AWS metadata service (http://169.254.169.254, ECS_CONTAINER_METADATA_URI/ECS_CONTAINER_METADATA_URI_V4 or https://kubernetes.default.svc respectively) to obtain metadata about the running process and its infrastructure.

An attacker who controls the configured endpoint(s), or who can intercept traffic to them (MiTM), can return an arbitrarily large response body. This causes unbounded heap allocation in the consuming process, leading to high transient memory pressure, garbage-collection stalls, or an OutOfMemoryException that terminates the process.

Impact

Denial of Service (DoS). An attacker can destabilize or crash the application by forcing unbounded memory allocation through the X-Ray sampling and/or EC2/ECS/EKS HTTP response paths.

Mitigating Factors

The default X-Ray sampling endpoint is http://localhost:2000, which limits remote exposure in default configurations.
Risk increases materially when operators configure the sampler to point at a remote or untrusted endpoint.

Patches

Fixed in OpenTelemetry.Sampler.AWS version 0.1.0-alpha.8 and OpenTelemetry.Resources.AWS version 1.15.1.

The fixes (#4100, #4122) introduce changes that introduce limits to HttpClient requests so that the response body is streamed rather than buffered entirely in memory.

Workarounds

Ensure the X-Ray sampling endpoint (http://localhost:2000 by default) is not accessible to untrusted parties.
Use network-level controls (firewall rules, mTLS, service mesh) to prevent Man-in-the-Middle (MitM) attacks on the sampling endpoint and/or EC2/ECS/EKS connection.
If using a remote endpoint, place it behind a reverse proxy that enforces a response body size limit.

Severity ?

5.9 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "NuGet",
        "name": "OpenTelemetry.Sampler.AWS"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.1.0-alpha.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "NuGet",
        "name": "OpenTelemetry.Resources.AWS"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.15.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-41173"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-23T21:44:31Z",
    "nvd_published_at": "2026-04-23T19:17:29Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\n`OpenTelemetry.Sampler.AWS` reads unbounded HTTP response bodies from a configured AWS X-Ray remote sampling endpoint into memory.\n\n`OpenTelemetry.Resources.AWS` reads unbounded HTTP response bodies from a configured AWS EC2/ECS/EKS remote instance metadata service endpoint into memory.\n\nBoth of these would allow an attacker-controlled endpoint or be acting as a Man-in-the-Middle (MitM) to cause excessive memory allocation and possible process termination (via Out of Memory (OOM)).\n\n### Details\n\n#### OpenTelemetry.Sampler.AWS\n\n`AWSXRaySamplerClient.DoRequestAsync` called `HttpClient.SendAsync` followed by `ReadAsStringAsync()`, which materializes the entire HTTP response body into a single in-memory string with no size limit. The sampling endpoint is configurable via `AWSXRayRemoteSamplerBuilder.SetEndpoint` (default: `http://localhost:2000`).\n\nAn attacker who controls the configured endpoint, or who can intercept traffic to it (MitM), can return an arbitrarily large response body. This causes unbounded heap allocation in the consuming process, leading to high transient memory pressure, garbage-collection stalls, or an `OutOfMemoryException` that terminates the process.\n\n#### OpenTelemetry.Resources.AWS\n\nThe [`AWSEC2Detector`](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/blob/171c6b81f88831641b56b470e6f92862e605013d/src/OpenTelemetry.Resources.AWS/AWSEC2Detector.cs), [`AWSECSDetector`](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/blob/171c6b81f88831641b56b470e6f92862e605013d/src/OpenTelemetry.Resources.AWS/AWSECSDetector.cs) and [`AWSEKSDetector`](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/blob/171c6b81f88831641b56b470e6f92862e605013d/src/OpenTelemetry.Resources.AWS/AWSEKSDetector.cs) classes all make HTTP requests to the relevant AWS metadata service (`http://169.254.169.254`, `ECS_CONTAINER_METADATA_URI`/`ECS_CONTAINER_METADATA_URI_V4` or `https://kubernetes.default.svc` respectively) to obtain metadata about the running process and its infrastructure.\n\nAn attacker who controls the configured endpoint(s), or who can intercept traffic to them (MiTM), can return an arbitrarily large response body. This causes unbounded heap allocation in the consuming process, leading to high transient memory pressure, garbage-collection stalls, or an `OutOfMemoryException` that terminates the process.\n\n### Impact\n\nDenial of Service (DoS). An attacker can destabilize or crash the application by forcing unbounded memory allocation through the X-Ray sampling and/or EC2/ECS/EKS HTTP response paths.\n\n### Mitigating Factors\n\n- The default X-Ray sampling endpoint is `http://localhost:2000`, which limits remote exposure in default configurations.\n- Risk increases materially when operators configure the sampler to point at a remote or untrusted endpoint.\n\n### Patches\n\nFixed in `OpenTelemetry.Sampler.AWS` version `0.1.0-alpha.8` and `OpenTelemetry.Resources.AWS` version `1.15.1`.\n\nThe fixes (#4100, #4122) introduce changes that introduce limits to `HttpClient` requests so that the response body is streamed rather than buffered entirely in memory.\n\n### Workarounds\n\n- Ensure the X-Ray sampling endpoint (`http://localhost:2000` by default) is not accessible to untrusted parties.\n- Use network-level controls (firewall rules, mTLS, service mesh) to prevent Man-in-the-Middle (MitM) attacks on the sampling endpoint and/or EC2/ECS/EKS connection.\n- If using a remote endpoint, place it behind a reverse proxy that enforces a response body size limit.",
  "id": "GHSA-28xm-prxc-5866",
  "modified": "2026-04-23T21:44:31Z",
  "published": "2026-04-23T21:44:31Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/open-telemetry/opentelemetry-dotnet-contrib/security/advisories/GHSA-28xm-prxc-5866"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41173"
    },
    {
      "type": "WEB",
      "url": "https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/4100"
    },
    {
      "type": "WEB",
      "url": "https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/4122"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/open-telemetry/opentelemetry-dotnet-contrib"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "OpenTelemetry.Sampler.AWS \u0026 OpenTelemetry.Resources.AWS have unbounded HTTP response body reads"
}

CVE-2026-41173 (GCVE-0-2026-41173)

Vulnerability from cvelistv5 – Published: 2026-04-23 18:22 – Updated: 2026-04-23 19:16

Title

Unbounded HTTP response body read in OpenTelemetry.Sampler.AWS

Summary

The AWS X-Ray Remote Sampler package provides a sampler which can get sampling configurations from AWS X-Ray. Prior to 0.1.0-alpha.8, OpenTelemetry.Sampler.AWS reads unbounded HTTP response bodies from a configured AWS X-Ray remote sampling endpoint into memory. AWSXRaySamplerClient.DoRequestAsync called HttpClient.SendAsync followed by ReadAsStringAsync(), which materializes the entire HTTP response body into a single in-memory string with no size limit. The sampling endpoint is configurable via AWSXRayRemoteSamplerBuilder.SetEndpoint (default: http://localhost:2000). An attacker who controls the configured endpoint, or who can intercept traffic to it (MitM), can return an arbitrarily large response body. This causes unbounded heap allocation in the consuming process, leading to high transient memory pressure, garbage-collection stalls, or an OutOfMemoryException that terminates the process. This vulnerability is fixed in 0.1.0-alpha.8.

Severity ?

5.9 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

GitHub_M

References

URL

Tags

	https://github.com/open-telemetry/opentelemetry-d…	x_refsource_CONFIRM
	https://github.com/open-telemetry/opentelemetry-d…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	open-telemetry	opentelemetry-dotnet-contrib	Affected: < 0.1.0-alpha.8

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-41173",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-23T19:11:43.914906Z",
                "version": "2.0.3"
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        "providerMetadata": {
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
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    "cna": {
      "affected": [
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          "vendor": "open-telemetry",
          "versions": [
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              "version": "\u003c 0.1.0-alpha.8"
            }
          ]
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      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The AWS X-Ray Remote Sampler package provides a sampler which can get sampling configurations from AWS X-Ray. Prior to 0.1.0-alpha.8, OpenTelemetry.Sampler.AWS reads unbounded HTTP response bodies from a configured AWS X-Ray remote sampling endpoint into memory.  AWSXRaySamplerClient.DoRequestAsync called HttpClient.SendAsync followed by ReadAsStringAsync(), which materializes the entire HTTP response body into a single in-memory string with no size limit. The sampling endpoint is configurable via AWSXRayRemoteSamplerBuilder.SetEndpoint (default: http://localhost:2000). An attacker who controls the configured endpoint, or who can intercept traffic to it (MitM), can return an arbitrarily large response body. This causes unbounded heap allocation in the consuming process, leading to high transient memory pressure, garbage-collection stalls, or an OutOfMemoryException that terminates the process. This vulnerability is fixed in 0.1.0-alpha.8."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 5.9,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
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      "problemTypes": [
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          "descriptions": [
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      "providerMetadata": {
        "dateUpdated": "2026-04-23T18:22:31.771Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
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      "references": [
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          "tags": [
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          "url": "https://github.com/open-telemetry/opentelemetry-dotnet-contrib/security/advisories/GHSA-28xm-prxc-5866"
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      ],
      "source": {
        "advisory": "GHSA-28xm-prxc-5866",
        "discovery": "UNKNOWN"
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      "title": "Unbounded HTTP response body read in OpenTelemetry.Sampler.AWS"
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  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
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    "dateReserved": "2026-04-17T16:34:45.525Z",
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    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-28XM-PRXC-5866

Summary

Details

OpenTelemetry.Sampler.AWS

OpenTelemetry.Resources.AWS

Impact

Mitigating Factors

Patches

Workarounds

CVE-2026-41173 (GCVE-0-2026-41173)

Tags

Sightings

Nomenclature