CVE-2026-116694
OpenTelemetry Python: Unbounded memory allocation in Jaeger baggage propagation
OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.0, JaegerPropagator.extract() in opentelemetry-propagator-jaeger processes inbound uberctx-* baggage values without entry, per-entry byte, or total-byte limits. Services that enable the optional Jaeger propagator can perform unnecessary CPU work and short-lived heap allocations when an untrusted carrier supplies numerous or oversized values, contributing to denial of service when transport-level limits do not constrain the input. Common default Python HTTP server limits reduce the practical impact, while custom getters, non-HTTP transports, or raised header limits increase exposure. This issue is fixed in version 1.45.0.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
6.3
OpenTelemetry Python: Unbounded memory allocation in Jaeger baggage propagation
OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.0, JaegerPropagator.extract() in opentelemetry-propagator-jaeger processes inbound uberctx-* baggage values without entry, per-entry byte, or total-byte limits. Services that enable the optional Jaeger propagator can perform unnecessary CPU work and short-lived heap allocations when an untrusted carrier supplies numerous or oversized values, contributing to denial of service when transport-level limits do not constrain the input. Common default Python HTTP server limits reduce the practical impact, while custom getters, non-HTTP transports, or raised header limits increase exposure. This issue is fixed in version 1.45.0.
- Record
CVE-2026-116694- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-770
- Updated
- 2026-11-02
EUVDEUVD-2026-111385
6.3
OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.0, JaegerPropagator.extract() in opentelemetry-propagator-jaeger processes inbound uberctx-* baggage values without entry, per-entry byte, or total-byte limits. Services that enable the optional Jaeger propagator can perform unnecessary CPU work and short-lived heap allocations when an untrusted carrier supplies numerous or oversized values, contributing to denial of service when transport-level limits do not constrain the input. Common default Python HTTP server limits reduce the practical impact, while custom getters, non-HTTP transports, or raised header limits increase exposure. This issue is fixed in version 1.45.0.
- Record
EUVD-2026-111385- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-f5m9-jfrj-jjj7
6.3
OpenTelemetry Python: Unbounded memory allocation in Jaeger baggage propagation
Summary
JaegerPropagator.extract() in opentelemetry-propagator-jaeger did not enforce limits when extracting inbound uberctx-* baggage headers. Attacker-controlled baggage could cause unnecessary CPU work and short-lived heap allocations while processing more data than the propagator should accept.
Impact
Services that enable the optional Jaeger propagator and accept untrusted inbound propagation headers may experience increased per-request resource usage. This can contribute to denial-of-service risk when transport-level limits are absent or configured above the baggage limits.
The practical impact for most Python web deployments is limited. The package must be installed separately, and the Jaeger propagator is not enabled by the default OpenTelemetry Python configuration.
Common Python web servers also constrain request headers before they reach the propagator:
- Gunicorn allows a maximum of 100 request-header fields and 8,190 bytes per field by default.
- Uvicorn’s h11 implementation limits its incomplete-event buffer to 16,384 bytes by default.
The risk is higher for non-HTTP transports, custom TextMapGetter implementations, or deployments where server and gateway limits have been increased or disabled.
The impact is limited to availability. This issue does not expose or modify telemetry data and does not allow code execution.
Patches
Versions of opentelemetry-propagator-jaeger earlier than 1.45.0 are affected.
Upgrade opentelemetry-propagator-jaeger to version 1.45.0 or later.
Version 1.45.0 limits extraction to 180 entries and 8,192 total bytes and skips entries larger than 4,096 bytes.
Credit
tonghuaroot
- Record
GHSA-f5m9-jfrj-jjj7- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-770
- Updated
- 2026-11-02
NVD
6.3
OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.0, JaegerPropagator.extract() in opentelemetry-propagator-jaeger processes inbound uberctx-* baggage values without entry, per-entry byte, or total-byte limits. Services that enable the optional Jaeger propagator can perform unnecessary CPU work and short-lived heap allocations when an untrusted carrier supplies numerous or oversized values, contributing to denial of service when transport-level limits do not constrain the input. Common default Python HTTP server limits reduce the practical impact, while custom getters, non-HTTP transports, or raised header limits increase exposure. This issue is fixed in version 1.45.0.
- Record
CVE-2026-116694- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-770
- Updated
- 2026-11-02
OSV
6.3
OpenTelemetry Python: Unbounded memory allocation in Jaeger baggage propagation
OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.0, JaegerPropagator.extract() in opentelemetry-propagator-jaeger processes inbound uberctx-* baggage values without entry, per-entry byte, or total-byte limits. Services that enable the optional Jaeger propagator can perform unnecessary CPU work and short-lived heap allocations when an untrusted carrier supplies numerous or oversized values, contributing to denial of service when transport-level limits do not constrain the input. Common default Python HTTP server limits reduce the practical impact, while custom getters, non-HTTP transports, or raised header limits increase exposure. This issue is fixed in version 1.45.0.
- Record
CVE-2026-116694- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-770
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-116694
6.3
OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.0, JaegerPropagator.extract() in opentelemetry-propagator-jaeger processes inbound uberctx-* baggage values without entry, per-entry byte, or total-byte limits. Services that enable the optional Jaeger propagator can perform unnecessary CPU work and short-lived heap allocations when an untrusted carrier supplies numerous or oversized values, contributing to denial of service when transport-level limits do not constrain the input. Common default Python HTTP server limits reduce the practical impact, while custom getters, non-HTTP transports, or raised header limits increase exposure. This issue is fixed in version 1.45.0.
- Record
DEBIAN-CVE-2026-116694- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Updated
- 2026-11-02
OSVGHSA-f5m9-jfrj-jjj7
6.3
OpenTelemetry Python: Unbounded memory allocation in Jaeger baggage propagation
Summary
JaegerPropagator.extract() in opentelemetry-propagator-jaeger did not enforce limits when extracting inbound uberctx-* baggage headers. Attacker-controlled baggage could cause unnecessary CPU work and short-lived heap allocations while processing more data than the propagator should accept.
Impact
Services that enable the optional Jaeger propagator and accept untrusted inbound propagation headers may experience increased per-request resource usage. This can contribute to denial-of-service risk when transport-level limits are absent or configured above the baggage limits.
The practical impact for most Python web deployments is limited. The package must be installed separately, and the Jaeger propagator is not enabled by the default OpenTelemetry Python configuration.
Common Python web servers also constrain request headers before they reach the propagator:
- Gunicorn allows a maximum of 100 request-header fields and 8,190 bytes per field by default.
- Uvicorn’s h11 implementation limits its incomplete-event buffer to 16,384 bytes by default.
The risk is higher for non-HTTP transports, custom TextMapGetter implementations, or deployments where server and gateway limits have been increased or disabled.
The impact is limited to availability. This issue does not expose or modify telemetry data and does not allow code execution.
Patches
Versions of opentelemetry-propagator-jaeger earlier than 1.45.0 are affected.
Upgrade opentelemetry-propagator-jaeger to version 1.45.0 or later.
Version 1.45.0 limits extraction to 180 entries and 8,192 total bytes and skips entries larger than 4,096 bytes.
Credit
tonghuaroot
- Record
GHSA-f5m9-jfrj-jjj7- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-770
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-116694
6.3
OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.0, JaegerPropagator.extract() in opentelemetry-propagator-jaeger processes inbound uberctx-* baggage values without entry, per-entry byte, or total-byte limits. Services that enable the optional Jaeger propagator can perform unnecessary CPU work and short-lived heap allocations when an untrusted carrier supplies numerous or oversized values, contributing to denial of service when transport-level limits do not constrain the input. Common default Python HTTP server limits reduce the practical impact, while custom getters, non-HTTP transports, or raised header limits increase exposure. This issue is fixed in version 1.45.0.
- Record
UBUNTU-CVE-2026-116694- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
opentelemetry-propagator-jaegerPyPI |
through 1.44.0 | 1.45.0 |
python-opentelemetryDebian:14 |
before 1.45.1-1, plus listed versions 1.35.0-21.38.0-11.38.0-21.39.1-11.39.1-2 Show 7 moreShow less1.40.0-11.41.0-11.41.0-21.42.1-11.43.0-11.44.0-11.44.0-2 |
1.45.1-1 |
opentelemetry-propagator-jaegerPyPI |
before 1.45.0, plus listed versions 0.17b01.0.01.0.0rc11.1.01.10.0 Show 45 moreShow less1.11.01.11.11.12.01.12.0rc11.12.0rc21.13.01.14.01.15.01.16.01.17.01.18.01.19.01.2.01.20.01.21.01.22.01.23.01.24.01.25.01.26.01.27.01.28.01.28.11.28.21.29.01.3.01.30.01.31.01.31.11.32.01.32.11.33.01.33.11.34.01.34.11.35.01.36.01.37.01.38.01.39.01.39.11.4.01.4.11.40.01.41.0 |
1.45.0 |
python-opentelemetryUbuntu:26.10 |
All versions, plus listed versions 1.39.1-21.42.1-11.43.0-11.44.0-11.44.0-2 |
None known |
python-opentelemetryUbuntu:26.04:LTS |
All versions, plus listed versions 1.38.0-11.38.0-21.39.1-11.39.1-2 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-116694 is a medium vulnerability (CVSS 6.3) in Open-telemetry Opentelemetry-python, published October 27, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.38%, the 31st percentile. Fixed in opentelemetry-propagator-jaeger 1.45.0.
References
github.com/open-telemetry/opentelemetry-python/security/advisories/GHSA-f5m9-jfrj-jjj7
github.com/open-telemetry/opentelemetry-python/pull/5556
github.com/open-telemetry/opentelemetry-python/commit/65c4eeb87cd3815dc795d3b5485e9ea0d5affcc7
github.com/open-telemetry/opentelemetry-python/releases/tag/v1.45.0
github.com/advisories/GHSA-f5m9-jfrj-jjj7
github.com/CVEProject/cvelistV5/tree/main/cves/2026/116xxx/CVE-2026-116694.json
Left out here: 14 versions. The JSON record has them.