# CVE-2026-48775: LangGraph Checkpoint: Unsafe JSON deserialization in checkpoint loading

> An attacker with write access to the SQLite checkpoint store can achieve code execution via unsafe JSON deserialization in LangGraph.

- **Severity:** Medium 6.8 (`CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Jun 2026
- **Updated:** 16 Jun 2026
- **Also known as:** CLSA-2026-1783472544, GHSA-fjqc-hq36-qh5p, PYSEC-2026-2573, ROOT-APP-PYPI-CVE-2026-48775

## What is CVE-2026-48775?

CVE-2026-48775 is a medium-severity unsafe deserialization vulnerability in langchain-ai langgraph, published on 16 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official 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.

Weakness: CWE-913 (Improper Control of Dynamically-Managed Code Resources), CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-48775?

3 open source packages ship an affected version, including langgraph-checkpoint. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `langgraph-checkpoint` | PyPI | All versions | 4.1.1 |
| `langgraph-checkpoint` | PyPI | All versions | 4.1.1 |
| `langgraph-checkpoint` | PyPI | All versions | 4.1.1 |

Products: Langchain Langgraph-Checkpoint.

## How do I fix CVE-2026-48775?

Upgrade langgraph-checkpoint to 4.1.1 or later.

## Is CVE-2026-48775 being exploited?

There is no known exploitation of CVE-2026-48775 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-48775 and fix it if it is affected.

What it is: CVE-2026-48775 is a medium-severity unsafe deserialization vulnerability in langchain-ai langgraph, published on 16 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-48775 in the wild and no public exploit code.

Affected packages and fixed versions:
- langgraph-checkpoint (PyPI): affected all versions; fixed in 4.1.1
- langgraph-checkpoint (PyPI): affected all versions; fixed in 4.1.1
- langgraph-checkpoint (PyPI): affected all versions; fixed in 4.1.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-48775/ (Markdown: https://insights.sbomify.com/CVE-2026-48775/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-48775
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-48775
- OSV: https://osv.dev/vulnerability/CVE-2026-48775

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-48775/
Summaries are generated and may contain mistakes; the official description above is the record.