🛡️ CVE-2026-45134 on PyPI (Root.io) — langchain

Distribution advisory

This page covers CVE-2026-45134 as tracked by PyPI (Root.io), for the package langchain. The fix is available in version 0.3.26+aikido.2; earlier versions remain affected.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. A user must be tricked into taking some action. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity low, availability none.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N

• Attack vector: Network — reachable from anywhere that can route to the service.
• Attack complexity: Low — the attack works reliably, with no preparation.
• Privileges required: None — an unauthenticated stranger can try it.
• User interaction: Required — someone has to click, open or visit something.
• Scope: Unchanged — the damage stays inside the vulnerable component.
• Confidentiality impact: High — total loss, or loss the attacker controls.
• Integrity impact: Low — limited, and the attacker does not choose what is affected.
• Availability impact: None.

Weakness class

ROOT-APP-PYPI-CVE-2026-45134 is classified as CWE-502: Deserialization of Untrusted Data. Serialised data from an untrusted source is reconstructed into objects, which can trigger code during the process.

Affected software

ROOT-APP-PYPI-CVE-2026-45134 is recorded against 6 packages.

• langchain (fixed in 0.3.26+aikido.2)
• langchain-classic (fixed in 1.0.2+aikido.2)
• langsmith (fixed in 0.7.21+aikido.7)
• rootio-langchain (fixed in 0.3.26+root.io.2)
• rootio-langchain-classic (fixed in 1.0.2+root.io.2)
• rootio-langsmith (fixed in 0.7.8+root.io.4)

Timeline and source

Published on 5 August 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

Other advisories for this package

langchain has other advisories on record. If you are patching this one, these are worth checking on the same host:

• ROOT-APP-PYPI-GHSA-gr75-jv2w-4656 (5.0 Medium, published 5 Aug 2026)
• ECHO-7afa-b4aa-5d4a (published 8 Jul 2026)
• CVE-2024-0243 (2.0 Low, published 7 Jul 2026)
• ECHO-a5b8-c61e-309a (published 1 Jul 2026)
• CVE-2023-32785 (9.5 Critical, published 29 Jun 2026)
• CVE-2026-55443 (5.1 Medium, published 22 Jun 2026)
• ROOT-APP-NPM-CVE-2025-68665 (8.0 High, published 4 Jun 2026)
• CVE-2026-44843 (8.2 High, published 26 May 2026)

Same weakness in other software

These advisories are the same class of weakness (CWE-502: Deserialization of Untrusted Data) in other software:

• CVE-2026-59940 (9.8 Critical, published 18 Aug 2026)
• CVE-2026-47058 (8.0 High, published 17 Aug 2026)

CVE-2026-45134 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Affected Packages

References