critical CVSS 9.9

CVE-2026-8476·Python vulnerability

IBM Langflow OSS 1.0.0 through 1.10.0 contain a critical remote code execution vulnerability in the disk-based caching mechanism. The AsyncDiskCache class uses Python's unsafe pickle.loads() function to deserialize cached objects from disk without validation, integrity verification, or authentication, enabling arbitrary code execution when malicious pickle payloads are processed. Attackers who can influence cached data through file system access, malicious workflow inputs, custom components, or API manipulation can achieve complete system compromise with the privileges of the Langflow server process.

Severity
critical
Software
Python
Fixed in
1.10.1
Published
2026-07-17

Affected versions

From: 1.0.0

Until: 1.10.1

Fixed in: 1.10.1

How to fix this CVE

Upgrade IBM Langflow OSS to version 1.10.1 or later immediately to patch the critical unsafe deserialization vulnerability in the AsyncDiskCache mechanism. This fix removes the dangerous pickle.loads() call and implements secure serialization practices. If you cannot upgrade immediately, restrict file system access to the Langflow cache directory and isolate the Langflow process with minimal privilege permissions.

sudo dnf update python3-langflow -y && sudo systemctl restart langflow

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check the installed Langflow version with: pip show langflow | grep Version
  2. Step 2: Verify if AsyncDiskCache is enabled in your Langflow configuration by checking ~/.langflow/config.yaml or environment variables for LANGFLOW_CACHE_TYPE
  3. Step 3: Search application logs for pickle deserialization errors with: grep -i 'pickle\|deserialize\|cache.*error' /var/log/langflow/*.log
  4. Step 4: Confirm the patch was applied by running: pip show langflow | grep Version and verifying output shows 1.10.1 or higher

FAQ

What is CVE-2026-8476?

CVE-2026-8476 is a critical remote code execution vulnerability in IBM Langflow OSS versions 1.0.0 through 1.10.0 that exploits unsafe pickle deserialization in the disk-based caching layer. An attacker with file system access or ability to inject malicious workflow inputs can execute arbitrary code with the privileges of the Langflow server process.

Is CVE-2026-8476 being actively exploited?

According to CISA KEV data, CVE-2026-8476 is not currently being actively exploited in the wild. However, no public exploit code is required due to the straightforward nature of pickle gadget chains, so defensive measures should be implemented immediately.

What versions of IBM Langflow OSS are affected by CVE-2026-8476?

Versions 1.0.0 through 1.10.0 are vulnerable. The fix is available in version 1.10.1 and all subsequent releases.

How do I check if my server is vulnerable to CVE-2026-8476?

Run 'pip show langflow | grep Version' to check your installed version. If the output shows any version from 1.0.0 to 1.10.0, your installation is vulnerable and requires immediate patching.

Does Defensia detect CVE-2026-8476?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If IBM Langflow OSS is installed on a monitored server, CVE-2026-8476 will appear in your dashboard with remediation steps and version validation.

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References

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