CVE-2026-48775: Langchain Langgraph-Checkpoint

Medium severity, CVSS 6.8. EPSS: 0.7% chance of exploitation in the next 30 days.

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.

Affected products

• Langchain Langgraph-Checkpoint: before 4.1.1 (fixed in 4.1.1)

Published 2026-06-16. Last modified 2026-06-24.