{"cve":"CVE-2026-81869","nvd":{"published":"2026-09-16T21:17:22.180","modified":"2026-09-30T17:43:24.057","status":"Awaiting Analysis","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.","cvss_v4":{"vector":"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","score":5.1},"cvss_v3":null,"cwes":["CWE-176","CWE-400"],"references":["https://github.com/open-telemetry/opentelemetry-go/commit/e016a78c9f5b24a1c2beeaad47686c2f2213f49a","https://github.com/open-telemetry/opentelemetry-go/issues/5996","https://github.com/open-telemetry/opentelemetry-go/pull/5997","https://github.com/open-telemetry/opentelemetry-go/releases/tag/sdk/v1.33.0","https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-p9f8-wvj8-2fg8"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:54:41.405518556+00:00"},"epss":{"cve":"CVE-2026-81869","score":0.0018,"percentile":0.07499,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-p9f8-wvj8-2fg8","url":"https://osv.dev/vulnerability/GHSA-p9f8-wvj8-2fg8","summary":"OpenTelemetry-Go: UTF-8 replacement rune bypasses attribute length truncation","modified":"2026-10-01T20:56:23.877100823Z","packages":[{"ecosystem":"Go","name":"go.opentelemetry.io/otel/sdk","purl":"pkg:golang/go.opentelemetry.io/otel/sdk","ranges":[">=1.10.0 <1.33.0"],"fixed":["1.33.0"]}]},{"id":"GO-2026-6616","url":"https://osv.dev/vulnerability/GO-2026-6616","summary":"OpenTelemetry-Go: UTF-8 replacement rune bypasses attribute length truncation in go.opentelemetry.io/otel/sdk","modified":"2026-10-01T20:45:17.224166882Z","packages":[{"ecosystem":"Go","name":"go.opentelemetry.io/otel/sdk","purl":"pkg:golang/go.opentelemetry.io/otel/sdk","ranges":[">=1.10.0 <1.33.0"],"fixed":["1.33.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}