{"api_version":"1","generated_at":"2026-09-22T08:49:58+00:00","cve":"CVE-2026-81869","urls":{"html":"https://cve.report/CVE-2026-81869","api":"https://cve.report/api/cve/CVE-2026-81869.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-81869","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-81869"},"summary":{"title":"OpenTelemetry-Go: UTF-8 replacement rune bypasses attribute length truncation","description":"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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-09-16 21:17:22","updated_at":"2026-09-17 15:16:52"},"problem_types":["CWE-176","CWE-400","CWE-176 CWE-176: Improper Handling of Unicode Encoding","CWE-400 CWE-400: Uncontrolled Resource 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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.","Type":"Description","Title":"OpenTelemetry-Go: UTF-8 replacement rune bypasses attribute leng"}]}}}