Is CVE-2026-34070 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-34070 being exploited in the wild.

How severe is CVE-2026-34070?

High severity, with a CVSS score of 7.5, published 31 March 2026.

Which products and versions are affected?

langchain-core (PyPI) ECOSYSTEM:introduced=0,fixed=1.2.22.

Is there a fix for CVE-2026-34070?

Yes. langchain-core (PyPI): upgrade to 1.2.22 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-34070 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-34070?

Check whether you run langchain-core (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-34070: LangChain langchain-core path traversal in prompt loading functions

CVE-2026-34070 · Severity: high · CVSS 7.5 · Published 2026-03-31

LangChain is a popular framework used to build applications powered by Artificial Intelligence and Large Language Models. A security flaw in its prompt-loading component allows attackers to read sensitive files from the server's filesystem, such as API keys, cloud credentials, and configuration files. This occurs when an application processes untrusted configuration data, potentially leading to a full compromise of service credentials and private data.

Technologies: langchain-core (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-34070 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-34070 being exploited in the wild.
How severe is CVE-2026-34070?: High severity, with a CVSS score of 7.5, published 31 March 2026.
Which products and versions are affected?: langchain-core (PyPI) ECOSYSTEM:introduced=0,fixed=1.2.22.
Is there a fix for CVE-2026-34070?: Yes. langchain-core (PyPI): upgrade to 1.2.22 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-34070 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-34070?: Check whether you run langchain-core (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

langchain-core (PyPI): upgrade to 1.2.22 or later
```
pip install "langchain-core>=1.2.22"
```

Technical details

A path traversal vulnerability (CWE-22) exists in langchain_core.prompts.loading within the load_prompt() and load_prompt_from_config() functions. These functions fail to validate file paths embedded in deserialized configuration dictionaries against directory traversal (../) or absolute path injection. An attacker can exploit this by providing a crafted configuration to read arbitrary files on the host, limited only by file extension checks (.txt, .json, .yaml). The vulnerability affects legacy, undocumented APIs that have been deprecated in favor of the more secure langchain_core.load serialization model. A patch is available in version 1.2.22 which introduces path validation and an explicit allow_dangerous_paths flag.

Affected products

LangChain langchain-core < 1.2.22
LangChain langchain < 1.2.22

Identifiers

CVE-2026-34070
GHSA-qh6h-p6c9-ff54
PYSEC-2026-2193

Timeline

2026-03-24: patched: Fix committed to repository and version 1.2.22 released.
2026-03-26: advisory: GitHub Security Advisory GHSA-qh6h-p6c9-ff54 published.
2026-03-31: disclosed: CVE-2026-34070 published to NVD.

References

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