What’s Vulnerable › Vulnerabilities

CVE-2026-29181: OpenTelemetry-Go multi-value `baggage` header extraction causes excessive allocations (remote dos amplification)

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.8% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-04-07 · updated 2026-09-11
• Weakness: CWE-770

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

• open-telemetry opentelemetry-go: from 1.36.0 before 1.41.0 — fixed in 1.41.0

How to fix

Upgrade to a fixed version: open-telemetry opentelemetry-go 1.41.0. Check the vendor advisory for mitigations.

References

• https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-mh2q-q3fh-2475
• 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

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