CVE-2026-25640
Description
A flaw was found in Pydantic AI. A remote attacker can exploit a path traversal vulnerability in the Pydantic AI web UI by crafting a malicious URL. This vulnerability arises from insufficient validation of the version query parameter, allowing the server to fetch and serve attacker-controlled HTML or JavaScript. If a victim clicks on such a link, malicious code can execute in their browser, potentially leading to the theft of sensitive client-side data, including chat history.
Statement
This IMPORTANT vulnerability in Pydantic AI, as included in Red Hat Enterprise Linux AI, involves a path traversal flaw in the web UI's CDN URL construction. An attacker can exploit this by crafting a malicious URL, leading to arbitrary JavaScript execution in a victim's browser if they click the link. This primarily affects deployments utilizing Agent.to_web or clai web for chat interfaces.
Mitigation
To reduce exposure, restrict network access to the Pydantic AI web interface. If the application is deployed on a remote server, configure firewall rules to limit access to trusted networks or localhost. This prevents untrusted clients from reaching the vulnerable component. After applying firewall changes, ensure the rules are persistent and the firewall service is reloaded.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.1 | 5.4 | 7.1 |
| Attack Vector | Network | Network | Network |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | None | None |
| User Interaction | Required | Required | Required |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | High | Low | High |
| Integrity Impact | Low | Low | Low |
| Availability Impact | None | None | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.
Integrity
Technical Impact: Modify Files or Directories
The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow an attacker to bypass authentication.
Confidentiality
Technical Impact: Read Files or Directories
The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing attacks in order to break into an account on the system.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the product from working at all and in the case of protection mechanisms such as authentication, it has the potential to lock out product users.
Frequently Asked Questions
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