Medium severity · published Oct 8, 2026
CVE-2026-107294
Pydantic AI: Unbounded memory use when downloading remote content via web_fetch or FileUrl
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 1.77.0 until 1.107.2 and 2.24.0, web_fetch_tool, the WebFetch local fallback, and remote FileUrl media downloads buffer the complete HTTP response body before enforcing content-size controls. An attacker-influenced URL can stream an arbitrarily large response that exhausts process memory and crashes the worker; affected media types include ImageUrl, DocumentUrl, VideoUrl, and AudioUrl. SSRF protections remain effective, and the impact is limited to availability. This issue is fixed in versions 1.107.2 and 2.24.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pydantic-ai · pydantic
>= 1.77.0, < 1.107.2; >= 2.0.0b1, < 2.24.0 · source: vendor
PY
pydantic-ai-slim · pydantic
>= 1.77.0, < 1.107.2; >= 2.0.0b1, < 2.24.0 · source: vendor
PA
Pydantic AI · Pydantic
1.77.0 before 1.107.2; 2.0.0 before 2.24.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-107294
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-107294
x_refsource_CONFIRM
https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-v2xh-2vp8-57h8
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/pull/7141
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/pull/7308
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/commit/7a64d049c3f5271a975cd1d64b2fa876d83ede1d
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/commit/e3824a58c82864ed26afb2887619834a4eb86cc8
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.2
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