CVE-2025-68664

CVE-2025-68664 is a critical-severity vulnerability in Langchain Langchain Core with a CVSS 3.x base score of 9.3. Its EPSS exploit-prediction score of 14% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-502.

Key facts

Description

LangChain is a framework for building agents and LLM-powered applications. Prior to versions 0.3.81 and 1.2.5, a serialization injection vulnerability exists in LangChain's dumps() and dumpd() functions. The functions do not escape dictionaries with 'lc' keys when serializing free-form dictionaries. The 'lc' key is used internally by LangChain to mark serialized objects. When user-controlled data contains this key structure, it is treated as a legitimate LangChain object during deserialization rather than plain user data. This issue has been patched in versions 0.3.81 and 1.2.5.

Frequently asked questions

What is CVE-2025-68664?
LangChain is a framework for building agents and LLM-powered applications. Prior to versions 0.3.81 and 1.2.5, a serialization injection vulnerability exists in LangChain's dumps() and dumpd() functions. The functions do not escape dictionaries with 'lc' keys when serializing free-form dictionaries. The 'lc' key is used internally by LangChain to mark serialized objects. When user-controlled data contains this key structure, it is treated as a legitimate LangChain object during deserialization rather than plain user data. This issue has been patched in versions 0.3.81 and 1.2.5.
How severe is CVE-2025-68664?
CVE-2025-68664 has a CVSS 3.x base score of 9.3, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2025-68664 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-68664?
CVE-2025-68664 affects Langchain Langchain Core. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-68664?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-68664 have an EU (EUVD) identifier?
Yes. CVE-2025-68664 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-204849.
When was CVE-2025-68664 published?
CVE-2025-68664 was published on 2025-12-23 and last updated on 2026-06-17.

References

Affected products (1)

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