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Fencer Vulns
high 8.2

CVE-2026-44843 json

LangChain: Unsafe deserialization of attacker-controlled LangChain objects through overly broad `load()` allowlists

published 2026-05-08 6 mo ago modified 2026-09-10 1 mo ago also GHSA-pjwx-r37v-7724 , PYSEC-2026-2564 , EUVD-2026-31976

cvss
8.2
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits
0
none known

Summary

LangChain is a framework for building agents and LLM-powered applications. Prior to 0.3.85 and 1.3.3, LangChain contains older runtime code paths that deserialize run inputs, run outputs, or other application-controlled payloads using overly broad object allowlists. These paths may call load() with allowed_objects="all". This does not enable arbitrary Python object deserialization, but it does allow any trusted LangChain-serializable object to be revived, which is broader than these runtime paths require. As a result, attacker-supplied LangChain serialized constructor dictionaries may cause trusted runtime paths to instantiate classes with untrusted constructor arguments. This vulnerability is fixed in 0.3.85 and 1.3.3.

Patch / fix

  • pypi langchain-core 0.3.85, 1.3.3
  • langchain langchain 0.3.85, 1.3.3

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-44843 updated cvss 8.2

langchain: LangChain: Information disclosure and data integrity compromise via insecure deserialization

  • Red Hat Exploit Intelligence exploit-intelligence-tech-preview/vulnerability-analysis-rhel9 Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-service-api-rhel9
    affected: workaround, no fix available
  • Red Hat Ansible Automation Platform 2 ansible-automation-platform-24/lightspeed-rhel8, ansible-automation-platform-25/lightspeed-rhel8, ansible-automation-platform-25/lightspeed-chatbot-rhel8
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Enterprise Linux AI (RHEL AI) 3 rhelai3/bootc-cuda-rhel9, rhelai3/bootc-rocm-rhel9, rhelai3/bootc-gaudi-rhel9, rhelai3/disk-image-cuda-rhel9
    affected: workaround, no fix available, no fix planned “Will not fix”
  • Red Hat Migration Toolkit for Applications 8.2 mta/mta-solution-server-rhel9 1784109883
    fixed: vendor fix RHSA-2026:43038
  • Red Hat OpenShift AI 3.3 rhoai/odh-trustyai-nemo-guardrails-server-rhel9 1789570674
    fixed: vendor fix RHSA-2026:73987
  • Red Hat OpenShift AI 3.4 rhoai/odh-autorag-rhel9 1786612637, rhoai/odh-llama-stack-core-rhel9 1786635926, rhoai/odh-trustyai-garak-lls-provider-dsp-rhel9 1791785804, rhoai/odh-trustyai-nemo-guardrails-server-rhel9 1787330585
    fixed: vendor fix RHSA-2026:60520
  • Red Hat Migration Toolkit for Applications 8.2 mta/mta-ui-rhel9 1783962515, mta/mta-cli-rhel9 1784211378, mta/mta-hub-rhel9 1784059743, mta/mta-rhel9-operator 1784219586, mta/mta-operator-bundle 1784220119, mta/mta-analyzer-addon-rhel9 1784163267, +7 more Red Hat OpenShift AI 3.3 rhoai/odh-cli-rhel9 1790070206, rhoai/rhai-cli-rhel9 1790070206, rhoai/odh-mlflow-rhel9 1789653606, rhoai/odh-trainer-rhel9 1790136369, rhoai/odh-maas-api-rhel9 1790131842, rhoai/odh-mlserver-rhel9 1789121365, +76 more Red Hat OpenShift AI 3.4 rhoai/odh-cli-rhel9 1787330837, rhoai/odh-cli-rhel9 1791509689, rhoai/rhai-cli-rhel9 1787330837, rhoai/rhai-cli-rhel9 1791509689, rhoai/odh-automl-rhel9 1786612415, rhoai/odh-automl-rhel9 1791535789, +202 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
5 mo ago

Exploit prediction

0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
GitHub 3.1 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
OSV 3.1 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

Affected packages

ecosystem package affected fixed in
pypi langchain-core
>=1.0.0, <1.3.3
<0.3.85
1.3.3
0.3.85

Affected products

  • langchain-ai langchain

Classification

Weakness
  • CWE-502 Deserialization of Untrusted Data

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.