CVE-2026-45134
Description
A flaw was found in the LangSmith Client SDKs. This vulnerability allows an external attacker to control the content of prompt manifests when a user pulls a public prompt from the LangSmith Hub. By exploiting the deserialization of untrusted data, an attacker could achieve high confidentiality impact, potentially leading to the disclosure of sensitive information and affecting the application's runtime behavior.
Statement
This Moderate impact vulnerability in LangSmith Client SDKs can lead to information disclosure and potential integrity loss. Red Hat products using these SDKs are affected when pulling public prompts from the LangSmith Hub, as untrusted manifest content may be deserialized. This could result in the execution of malicious LangChain objects or model configurations, requiring user interaction for exploitation.
Mitigation
To mitigate this vulnerability, avoid pulling public prompts from the LangSmith Hub using the LangSmith Client SDKs without explicit trust. The SDK provides a `dangerously_pull_public_prompt` flag (Python) or `dangerouslyPullPublicPrompt` (JS/TS) that must be set to `True` to enable pulling public prompts by `owner/name`. Do not enable this flag unless the prompt's contents have been independently reviewed and trusted. Additionally, when pulling prompts, avoid setting `include_model=True` or `secrets_from_env=True` if the prompt source is untrusted, as these options expand the deserialization allowlist and allow reading environment variables.
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 | N/A | 7.1 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/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
Technical Impact: Modify Application Data; Unexpected State
Attackers can modify unexpected objects or data that was assumed to be safe from modification. Deserialized data or code could be modified without using the provided accessor functions, or unexpected functions could be invoked.
Availability
Technical Impact: DoS: Resource Consumption (CPU)
If a function is making an assumption on when to terminate, based on a sentry in a string, it could easily never terminate.
Other
Technical Impact: Varies by Context
The consequences can vary widely, because it depends on which objects or methods are being deserialized, and how they are used. Making an assumption that the code in the deserialized object is valid is dangerous and can enable exploitation. One example is attackers using gadget chains to perform unauthorized actions, such as generating a shell.
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