CVE-2026-29181

OpenTelemetry-Go multi-value `baggage` header extraction causes excessive allocations (remote dos amplification)

OpenTelemetry-Go is the Go implementation of OpenTelemetry. From 1.36.0 to 1.40.0, multi-value baggage: header extraction parses each header field-value independently and aggregates members across values. This allows an attacker to amplify cpu and allocations by sending many baggage: header lines, even when each individual value is within the 8192-byte per-value parse limit. This vulnerability is fixed in 1.41.0.

Affected

open-telemetry · opentelemetry-go

CVSS v3.1 CNA

7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

0.87% chance of exploitation in the next 30 days, 58th percentile

Published

2026-04-07

Updated

2026-09-17

Proof-of-concept exploits (1)

• advisories/GHSA-mh2q-q3fh-2475

Security advisories

• open-telemetry/opentelemetry-go/security/advisories/GHSA-mh2q-q3fh-2475

References

• CVE Record
• NVD entry