Unsafe Deserialization in langgraph-checkpoint (CVE-2026-48775)
Summary
Vulnerability in langgraph-checkpoint (CVE-2026-48775). Successful exploitation can lead to full system takeover. Exploitable via JsonPlusSerializer. Mitigation: upgrade to 4.1.1 or later.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-48775 has been found in langgraph-checkpoint.
Attackers can target a specific entry point like JsonPlusSerializer over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 6.8/10.
What to do: upgrade langgraph-checkpoint to 4.1.1 or later.
If unsure, ask your IT team or search "langgraph-checkpoint CVE-2026-48775" on the vendor's site.
CVE-2026-48775 (langgraph-checkpoint) — CWE-502 / CVSS v3 6.8
Attack vector: adjacent-network / no user interaction
Attack surface: JsonPlusSerializer / PostgresSaver / SqliteSaver / None
Patched: 4.1.1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Unsafe deserialization (CWE-502) exists in langgraph-checkpoint. Attackers reach the vulnerable code path via JsonPlusSerializer.
Check the vendor advisory for the affected versions of langgraph-checkpoint. Attack surface: JsonPlusSerializer / PostgresSaver / SqliteSaver / None.
Severity: Medium (CVSS 6.8/10). Successful exploitation can lead to full system takeover.
Update to 4.1.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'langgraph-checkpoint' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'langgraph-checkpoint' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
langgraph-checkpointを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade langgraph-checkpoint to 4.1.1ステージング環境で 4.1.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- web github.com