CVE-2026-107289
Pydantic AI: SSRF cloud-metadata blocklist bypass via IPv6 zone identifier (incomplete fix for CVE-2026-46678 and CVE-2026-48782)
No known exploitation. EPSS puts it in the 24th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
- Pydantic-aiAffected: >= 1.56.0, < 1.107.6Upgrade to: not statedAffected: >= 2.0.0b1, < 2.44.0Upgrade to: not statedStated by: CVE record
- Pydantic-ai-slimAffected: >= 1.56.0, < 1.107.6Upgrade to: not statedAffected: >= 2.0.0b1, < 2.44.0Upgrade to: not statedStated by: CVE record
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.3% chance of exploitation activity in the next 30 days, which ranks it in the 24th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
8 events over 5 days, from the signal feeds we watch.
- Patch availableworkaround available, record updated
- Publishedweakness classified, att&ck mapped, record updated, record updated
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
Scored 6.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Command and ControlT1090Proxyhigh confidence
- Initial AccessT1190Exploit Public-Facing Applicationmedium confidence
Sources
References in the record
- github.com/pydantic/pydantic-ai/security/advisories/GHSA-vmxc-h2x2-jmf3
- github.com/pydantic/pydantic-ai/pull/8401
- github.com/pydantic/pydantic-ai/pull/8402
And 4 more references. See all after sign-in
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