GHSA-mhr3-j7m5-c7c9: langgraph-checkpoint (CVE-2026-27794)

Package	Ecosystem	Affected	Fixed in
langgraph-checkpoint	PyPI	<4.0.0	4.0.0

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

LangGraph's langgraph-checkpoint package, versions before 4.0.0, is vulnerable to remote code execution through its cache layer, where pickle deserialization can run on cache entries when the cache is enabled and nodes opt into caching. An attacker would need write access to the configured cache backend, such as a weakly protected Redis instance or a writable SQLite cache file, and could then execute arbitrary code in the LangGraph process. Upgrade langgraph-checkpoint to version 4.0.0 or later, which disables pickle fallback by default.

Written 6 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.6	Medium	3.1	CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0084, the 58th percentile, on 13 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 15:01 UTC First seen by agentprime
31 Oct 2026, 15:01 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.