CVE-2026-81869
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 4.0
- 5.1
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 - EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 7% of CVEs (scores of 2026-10-25)
- CWEs
- CWE-176, CWE-400
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-p9f8-wvj8-2fg8 | Go | go.opentelemetry.io/otel/sdk | >=1.10.0 <1.33.0 | 1.33.0 |
| GO-2026-6616 | Go | go.opentelemetry.io/otel/sdk | >=1.10.0 <1.33.0 | 1.33.0 |
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