CVE-2025-68664 is a critical-severity (CVSS 9.3) Deserialization of Untrusted Data vulnerability in langchain-core. 2 public exploit references exist, so weaponization risk is real. A fix is available for langchain-core — see the affected versions and patch details below.
LangChain serialization injection vulnerability enables secret extraction in dumps/loads APIs
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-68664.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2025-68664 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 376,715 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
langchain-core🐍langchain-coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | langchain-core | ≥ 1.0.0&&< 1.2.5 | 1.2.5pip install --upgrade 'langchain-core==1.2.5' |
| 🐍PyPI | langchain-core | all versions | 0.3.81pip install --upgrade 'langchain-core==0.3.81' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
LangChain Core 1.2.4 - SSTI/RCE
by banyamer · Apr 29, 2026
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for langchain-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update langchain-core to 1.2.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-68664 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-68664 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-68664. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This vulnerability is rated Critical for Red Hat products. A serialization injection flaw in LangChain's `dumps()` and `dumpd()` functions allows remote attackers to achieve arbitrary code execution. This occurs when user-controlled data containing the internal 'lc' key is improperly deserialized as a legitimate…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Ansible Automation Platform 2.4 | ansible-automation-platform-24/lightspeed-rhel8:1767342459 | RHSA-2026:0406 |
| Red Hat Ansible Automation Platform 2.5 | ansible-automation-platform-25/lightspeed-chatbot-rhel8:1767224443 | RHSA-2026:0409 |
| Red Hat Ansible Automation Platform 2.6 | ansible-automation-platform-26/lightspeed-rhel9:1767625654 | RHSA-2026:0408 |
| Red Hat OpenShift Lightspeed 1.0.11 | openshift-lightspeed/lightspeed-service-api-rhel9:1769058587 | RHSA-2026:1610 |
Frequently Asked Questions
Is CVE-2025-68664 in your dependencies?
O3 Security finds CVE-2025-68664 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.