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.
Affected products
opentelemetry: opentelemetry
References9
- github.com/open-telemetry/opentelemetry-go/security/advisories/… ExploitVendor Advisory
- access.redhat.com/errata/RHSA-2026:25271
- access.redhat.com/errata/RHSA-2026:47735
- access.redhat.com/errata/RHSA-2026:61314
- access.redhat.com/errata/RHSA-2026:63140
- access.redhat.com/errata/RHSA-2026:66521
- access.redhat.com/security/cve/CVE-2026-29181
- bugzilla.redhat.com/show_bug.cgi?id=2456252
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-29181…
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 58 · as of 12 November 2026
- CWE
- CWE-770
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