LangGraph Checkpoint defines the base interface for LangGraph checkpointers. Prior to version 4.0.0, a Remote Code Execution vulnerability exists in LangGraph's caching layer when applications enable cache backends that inherit from BaseCache and opt nodes into caching via CachePolicy. Prior to langgraph-checkpoint 4.0.0, BaseCache defaults to JsonPlusSerializer(pickle_fallback=True). When msgpack serialization fails, cached values can be deserialized via pickle.loads(...). Caching is not enabled by default. Applications are affected only when the application explicitly enables a cache backend (for example by passing cache=... to StateGraph.compile(...) or otherwise configuring a BaseCache implementation), one or more nodes opt into caching via CachePolicy, and the attacker can write to the cache backend (for example a network-accessible Redis instance with weak/no auth, shared cache infrastructure reachable by other tenants/services, or a writable SQLite cache file). An attacker must be able to write attacker-controlled bytes into the cache backend such that the LangGraph process later reads and deserializes them. This typically requires write access to a networked cache (for example a network-accessible Redis instance with weak/no auth or shared cache infrastructure reachable by other tenants/services) or write access to local cache storage (for example a writable SQLite cache file via permissive file permissions or a shared writable volume). Because exploitation requires write access to the cache storage layer, this is a post-compromise / post-access escalation vector. LangGraph Checkpoint 4.0.0 patches the issue.
CVE-2026-27794
“—” beside the score: it is equal to NVD's CVSS score.
Score 6.6 from GitHub Security Advisory (severity: MODERATE) published 2026-02-25. NVD baseline CVSS 6.6; sources differ by 0.0.
Also known asEUVD-2026-8696 (ENISA EUVD) · GHSA-mhr3-j7m5-c7c9 (GitHub Security Advisories) · PYSEC-2026-2574 (OSV.dev)Source: ENISA EUVD
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v3
- 6.6
- EG Score
- 6.6MEDIUMmedium confidence
- EG Risk
- 30EG Risk 30/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity66% × 45%Impact severity (EG Severity): CVSS 6.6 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation0.8% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines. - EPSS PROB
- 0.8%
- EPSS %ILE
- 57th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (6.6): severity, escalated by confirmed exploitation. This CVE's 6.6 is its impact severity (EG Severity), not escalated.
- EG Severity
- 6.6 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.8% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-31). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
February 25, 2026
Last Modified
June 17, 2026
Advisory Details (4)
Auto-updated Aug 4, 2026ZDI-CAN-28385: LangChain LangGraph BaseCache Deserialization of Untrusted Data Remote Code Execution Vulnerability · Advisory · langchain-ai/langgraph · GitHub
https://github.com/langchain-ai/langgraph/security/advisories/GHSA-mhr3-j7m5-c7c9langgraph-checkpoint==4.0.0
Patch available: langchain-ai/langgraph checkpoint==4.0.0
https://github.com/langchain-ai/langgraph/releases/tag/checkpoint%3D%3D4.0.0fix: flip default on base cache
Patch available: langchain-ai/langgraph sdk==0.3.14 (PR #6677 merged 2026-01-12)
https://github.com/langchain-ai/langgraph/pull/6677commit f91d79d0c869 (langchain-ai/langgraph)
Patch available: langchain-ai/langgraph sdk==0.3.14 (contains commit f91d79d0c869)
https://github.com/langchain-ai/langgraph/commit/f91d79d0c86932ded6e3b9f195d5a0bbd5aef99cPatch Availability(1)
| Vendor / Ecosystem | Fix (by version range) / Patch | Released | Source |
|---|---|---|---|
| pip | langgraph-checkpoint @ 4.0.0 (fixes < 4.0.0) | — | ghsa |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(1 across 1 ecosystem)
PyPI(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| langgraph-checkpoint | 1.0.0 ... 3.0.1 (46 versions) |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 10× in last 7d / 41× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 96 of 228 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 4 repeat rows among the latest 100 are merged into the row they repeat. The 132 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-11-02 16:44 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-11-01 07:56 UTCGHSA enrichmentGHSA-mhr3-j7m5-c7c9 · GitHub severity MODERATE · GitHub CVSS 6.6
- 2026-11-01 07:56 UTCEG score recompute
- 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-31 00:25 UTCOSV refresh
- 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.8% · 57th percentile
- 2026-10-25 14:38 UTCEG score recompute
- 2026-10-24 16:32 UTCEPSS rescoreEPSS 1.1% · 65th percentile
- 2026-10-23 16:31 UTCEPSS rescoreEPSS 1.1% · 65th percentile
- 2026-10-23 04:22 UTCEG score recompute
- 2026-10-22 16:34 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-10-21 16:32 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-10-20 16:32 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-10-19 16:31 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-10-18 16:31 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-10-18 03:51 UTCEG score recompute
- 2026-10-17 16:33 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-10-16 16:41 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-10-15 16:31 UTCEPSS rescoreEPSS 1.0% · 61st percentile
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- 2026-10-14 16:32 UTCEPSS rescoreEPSS 1.0% · 61st percentile
- 2026-10-13 16:34 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-12 16:33 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-12 16:17 UTCEG score recompute
- 2026-10-11 19:59 UTCEG score recompute
- 2026-10-11 17:12 UTCEG score recompute
- 2026-10-11 14:44 UTCEG score recompute
- 2026-10-11 13:48 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-10 20:00 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-09 20:07 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-08 17:11 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-08 13:54 UTCOSV refresh
- 2026-10-07 23:47 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-06 15:17 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-05 17:42 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-04 23:21 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-03 14:25 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-10-01 19:49 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-09-30 15:03 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-09-28 13:51 UTCEPSS rescoreEPSS 1.0% · 60th percentile
- 2026-09-26 15:58 UTCEPSS rescoreEPSS 1.0% · 59th percentile
- 2026-09-26 00:26 UTCEPSS rescoreEPSS 1.0% · 59th percentile
- 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.7% · 51st percentile
- 2026-09-18 19:36 UTCOSV refresh
- 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.7% · 51st percentile
- 2026-09-17 19:30 UTCEPSS rescoreEPSS 0.7% · 51st percentile
- 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.7% · 51st percentile
- 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.7% · 51st percentile
- 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.7% · 51st percentile
- 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.7% · 51st percentile
- 2026-09-11 14:52 UTCEPSS rescoreEPSS 0.7% · 51st percentile
- 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.7% · 50th percentile
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- 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.7% · 50th percentile
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- 2026-09-02 14:11 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-09-01 13:53 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-09-01 04:39 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-30 22:47 UTCOSV refresh
- 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-25 13:48 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-19 17:03 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.7% · 50th percentile
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- 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.7% · 50th percentile
- 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-14 09:00 UTCEG score recompute
- 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-13 01:00 UTCEG score recompute
- 2026-08-12 13:50 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-11 23:56 UTCEG score recompute
- 2026-08-11 13:42 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-11 00:00 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-10 09:05 UTCEG score recompute
- 2026-08-09 13:46 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-09 08:38 UTCEG score recompute
- 2026-08-08 16:37 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-07 20:42 UTCEG score recompute
- 2026-08-06 13:46 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-06 03:00 UTCEG score recompute
- 2026-08-05 19:17 UTCEPSS rescoreEPSS 0.7% · 49th percentile
- 2026-08-04 15:10 UTCEPSS rescoreEPSS 0.7% · 49th percentile
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Frequently asked(5)
What is CVE-2026-27794?
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What is the CVSS score of CVE-2026-27794?
How do I remediate CVE-2026-27794?
Dependency Blast Radius
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