CVE-2026-48775: langchain-ai langgraph Deserialization of Untrusted Data

Vulnerability summary

CVE-2026-48775 is a medium (CVSS 6.8) Deserialization of Untrusted Data vulnerability in langchain-ai langgraph. EPSS estimates a 0.69% chance of exploitation in the next 30 days, higher than 51.7% of scored vulnerabilities.

Timeline

1. 16-06-2026
   PublishedVulnerability first disclosed.
2. 16-06-2026
   Last modifiedVulnerability information updated.

Description

LangGraph SQLite Checkpoint is an implementation of LangGraph CheckpointSaver that uses SQLite DB (both sync and async, via aiosqlite). In versions 4.1.0 and prior, the JsonPlusSerializer can reconstruct Python objects from JSON checkpoint payloads. Under conditions where someone could modify checkpoint bytes at rest in the backing store, the deserialization path could reconstruct objects beyond what the application expects, which could in turn result in code execution at checkpoint load time. This is a defense-in-depth issue. The affected behavior is reachable only when checkpoint bytes at rest in the backing store can be modified by an unauthorized party. In most deployments that prerequisite already implies a serious incident; the additional concern is turning "checkpoint-store write access" into code execution in the application runtime. This issue has been fixed in version 4.1.1.

• CWE-502Deserialization of Untrusted DataThe product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
• CWE-913Improper Control of Dynamically-Managed Code ResourcesThe product does not properly restrict reading from or writing to dynamically-managed code resources such as variables, objects, classes, attributes, functions, or executable instructions or statements.