CVE-2026-29181
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.79%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.79% probability · 54th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-770
- Affected
- opentelemetry/opentelemetry
- Source
- security-advisories@github.com
References
- https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-mh2q-q3fh-2475Exploit, Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:25271
- https://access.redhat.com/errata/RHSA-2026:47735
- https://access.redhat.com/errata/RHSA-2026:61314
- https://access.redhat.com/errata/RHSA-2026:63140
- https://access.redhat.com/errata/RHSA-2026:66521
- https://access.redhat.com/security/cve/CVE-2026-29181
- https://bugzilla.redhat.com/show_bug.cgi?id=2456252
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-29181.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.