Vulnerability-Lookup

UBUNTU-CVE-2026-81869 (CVE-2026-81869)

Vulnerability from osv_ubuntu – Published: 2026-09-18 00:00 – Updated: 2026-09-18 00:00 – Source website

Details

OpenTelemetry-Go is the Go implementation of OpenTelemetry. From version 1.10.0 until 1.33.0, the sdk/trace/span.go attribute truncation path can fail to enforce AttributeValueLengthLimit for string and string-slice attributes containing the valid Unicode replacement character U+FFFD. safeTruncateValidUTF8 treats the valid replacement rune as invalid UTF-8 and returns the original input, while strings.ToValidUTF8 leaves that valid rune unchanged, so a second safeTruncate attempt can also return the oversized value. An attacker who controls span attribute content can retain values longer than the configured limit, increasing per-span memory use and weakening denial-of-service protection in the instrumented process. This issue is fixed in version 1.33.0.

Severity

5.1 (Medium)


                    
                      CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-81869	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-81869	REPORT
	https://github.com/open-telemetry/opentelemetry-g…	REPORT
	https://github.com/open-telemetry/opentelemetry-g…	REPORT
	https://github.com/open-telemetry/opentelemetry-g…	REPORT
	https://github.com/open-telemetry/opentelemetry-g…	REPORT
	https://github.com/open-telemetry/opentelemetry-g…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-opentelemetry-otel-dev",
            "binary_version": "1.1.0-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "golang-opentelemetry-otel",
        "purl": "pkg:deb/ubuntu/golang-opentelemetry-otel@1.1.0-2?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.1.0-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-opentelemetry-otel-dev",
            "binary_version": "1.16.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "golang-opentelemetry-otel",
        "purl": "pkg:deb/ubuntu/golang-opentelemetry-otel@1.16.0-1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.16.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-opentelemetry-otel-dev",
            "binary_version": "1.31.0-6"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "golang-opentelemetry-otel",
        "purl": "pkg:deb/ubuntu/golang-opentelemetry-otel@1.31.0-6?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.31.0-4",
        "1.31.0-5",
        "1.31.0-6"
      ]
    }
  ],
  "aliases": [],
  "details": "OpenTelemetry-Go is the Go implementation of OpenTelemetry. From version 1.10.0 until 1.33.0, the sdk/trace/span.go attribute truncation path can fail to enforce AttributeValueLengthLimit for string and string-slice attributes containing the valid Unicode replacement character U+FFFD. safeTruncateValidUTF8 treats the valid replacement rune as invalid UTF-8 and returns the original input, while strings.ToValidUTF8 leaves that valid rune unchanged, so a second safeTruncate attempt can also return the oversized value. An attacker who controls span attribute content can retain values longer than the configured limit, increasing per-span memory use and weakening denial-of-service protection in the instrumented process. This issue is fixed in version 1.33.0.",
  "id": "UBUNTU-CVE-2026-81869",
  "modified": "2026-09-18T00:00:00Z",
  "published": "2026-09-18T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-81869"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-81869"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/open-telemetry/opentelemetry-go/commit/e016a78c9f5b24a1c2beeaad47686c2f2213f49a"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/open-telemetry/opentelemetry-go/issues/5996"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/open-telemetry/opentelemetry-go/pull/5997"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/open-telemetry/opentelemetry-go/releases/tag/sdk/v1.33.0"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-p9f8-wvj8-2fg8"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-81869"
  ]
}

CVE-2026-81869 (GCVE-0-2026-81869)

Vulnerability from cvelistv5 – Published: 2026-09-16 20:41 – Updated: 2026-09-17 14:15

Title

OpenTelemetry-Go: UTF-8 replacement rune bypasses attribute length truncation

Summary

Severity

5.1 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-17 14:15 UTC

CWE

CWE-176 - Improper Handling of Unicode Encoding
CWE-400 - Uncontrolled Resource Consumption

Assigner

GitHub_M mitre root

References

5 references

URL	Tags
https://github.com/open-telemetry/opentelemetry-g…	x_refsource_CONFIRM
https://github.com/open-telemetry/opentelemetry-g…	x_refsource_MISC
https://github.com/open-telemetry/opentelemetry-g…	x_refsource_MISC
https://github.com/open-telemetry/opentelemetry-g…	x_refsource_MISC
https://github.com/open-telemetry/opentelemetry-g…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
open-telemetry	opentelemetry-go	Affected: >= 1.10.0, < 1.33.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-81869",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-17T14:15:41.862542Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-17T14:15:51.501Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-p9f8-wvj8-2fg8"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "opentelemetry-go",
          "vendor": "open-telemetry",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 1.10.0, \u003c 1.33.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "OpenTelemetry-Go is the Go implementation of OpenTelemetry. From version 1.10.0 until 1.33.0, the sdk/trace/span.go attribute truncation path can fail to enforce AttributeValueLengthLimit for string and string-slice attributes containing the valid Unicode replacement character U+FFFD. safeTruncateValidUTF8 treats the valid replacement rune as invalid UTF-8 and returns the original input, while strings.ToValidUTF8 leaves that valid rune unchanged, so a second safeTruncate attempt can also return the oversized value. An attacker who controls span attribute content can retain values longer than the configured limit, increasing per-span memory use and weakening denial-of-service protection in the instrumented process. This issue is fixed in version 1.33.0."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 5.1,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-176",
              "description": "CWE-176: Improper Handling of Unicode Encoding",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-400",
              "description": "CWE-400: Uncontrolled Resource Consumption",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-16T20:41:15.806Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-p9f8-wvj8-2fg8",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-p9f8-wvj8-2fg8"
        },
        {
          "name": "https://github.com/open-telemetry/opentelemetry-go/issues/5996",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/open-telemetry/opentelemetry-go/issues/5996"
        },
        {
          "name": "https://github.com/open-telemetry/opentelemetry-go/pull/5997",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/open-telemetry/opentelemetry-go/pull/5997"
        },
        {
          "name": "https://github.com/open-telemetry/opentelemetry-go/commit/e016a78c9f5b24a1c2beeaad47686c2f2213f49a",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/open-telemetry/opentelemetry-go/commit/e016a78c9f5b24a1c2beeaad47686c2f2213f49a"
        },
        {
          "name": "https://github.com/open-telemetry/opentelemetry-go/releases/tag/sdk/v1.33.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/open-telemetry/opentelemetry-go/releases/tag/sdk/v1.33.0"
        }
      ],
      "source": {
        "advisory": "GHSA-p9f8-wvj8-2fg8",
        "discovery": "UNKNOWN"
      },
      "title": "OpenTelemetry-Go: UTF-8 replacement rune bypasses attribute length truncation"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-81869",
    "datePublished": "2026-09-16T20:41:15.806Z",
    "dateReserved": "2026-08-27T17:48:42.120Z",
    "dateUpdated": "2026-09-17T14:15:51.501Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.