Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 0.3.4 until 1.107.4 and 2.27.1, OpenTelemetry instrumentation configured with InstrumentationSettings(include_content=False) can export retry prompts outside tool calls in gen_ai.input.messages and pydantic_ai.all_messages. Agents using NativeOutput, PromptedOutput, or output validators on text output can therefore disclose validation feedback, including invalid model values quoted by that feedback, to readers of the telemetry backend. Tool-call retries and deployments that do not use include_content=False are not affected by this specific path. This issue is fixed in versions 1.107.4 and 2.27.1.
https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-3gh4-cghq-f8v4
https://github.com/pydantic/pydantic-ai/releases/tag/v2.27.1
https://github.com/pydantic/pydantic-ai/pull/7357
https://github.com/pydantic/pydantic-ai/commit/fe9dbed7b7ccf7e7128b5786886e4441f6f5594f
Published: 2026-10-08
Updated: 2026-10-08
Base Score: 6.4
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:P
Severity: Medium
Base Score: 9.8
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 2.3
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Severity: Low
EPSS: 0.00336