Medium severity · published Oct 8, 2026
CVE-2026-107289
Pydantic AI: SSRF cloud-metadata blocklist bypass via IPv6 zone identifier (incomplete fix for CVE-2026-46678 and CVE-2026-48782)
6.8
CVSS
0.4%
EPSS
No
On KEV
Description
Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 1.56.0 until 1.107.6 and 2.44.0, applications that opt attacker-influenced URLs into local network access through FileUrl with force_download='allow-local' or web_fetch_tool with allow_local_urls=True can bypass the cloud-metadata blocklist by appending an IPv6 zone identifier to an IPv6 metadata address. IPv6Address equality and hashing include the zone identifier, so the blocklist comparison fails even though the network stack ignores the zone on a non-link-local destination and reaches the metadata service, potentially exposing cloud IAM credentials. The opt-in settings are disabled by default, and the issue requires an IPv6-enabled environment. This issue is fixed in versions 1.107.6 and 2.44.0.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pydantic-ai · pydantic
>= 1.56.0, < 1.107.6; >= 2.0.0b1, < 2.44.0 · source: vendor
PY
pydantic-ai-slim · pydantic
>= 1.56.0, < 1.107.6; >= 2.0.0b1, < 2.44.0 · source: vendor
PA
Pydantic AI · Pydantic
1.56.0 before 1.107.6; 2.0.0 before 2.44.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-107289
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-107289
x_refsource_CONFIRM
https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-vmxc-h2x2-jmf3
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/pull/8401
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/pull/8402
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/commit/02157e1b87bd45d3f2e111ce07afdf89f9fb0e5b
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/commit/4da70591460f51a8c4f128eaeef70a33340dbd55
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.6
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