How severe is CVE-2026-21445?

No CVSS score has been assigned to CVE-2026-21445 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-21445?

CVE-2026-21445 affects the following packages: langflow-base (PyPI), langflow (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2026-21445?

Update langflow-base to 0.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-21445 is resolved across your whole dependency graph.

How do I detect CVE-2026-21445 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for langflow-base. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2026-21445 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2026-21445?

O3 pinpoints whether CVE-2026-21445 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2026-21445 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-21445 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-21445?

CVE-2026-21445 has an EPSS (Exploit Prediction Scoring System) score of 21.3%, placing it in the 97th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score warrants monitoring and prompt remediation.

Is there exploit tooling available for CVE-2026-21445?

A Nuclei detection template exists for CVE-2026-21445, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2026-21445 published, and has it been updated?

CVE-2026-21445 was published on January 2, 2026 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2026-21445: Langflow Missing Authentication on Critical API…

EPSS Exploitation Probability

via FIRST.org ↗

21.3%probability of exploitation in next 30 days

Moderate Risk97th percentile+12.25%

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.

Blast Radius

2 pkgs affected

🐍langflow-base🐍langflow

Real-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

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to version 1.7.0.dev45, multiple critical API endpoints in Langflow are missing authentication controls. The issue allows any unauthenticated user to access sensitive user conversation data, transaction histories, and perform destructive operations including message deletion. This affects endpoints handling personal data and system operations that should require proper authorization. Version 1.7.0.dev45 contains a patch.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`langflow-base`	all versions	0.7.1
🐍PyPI	`langflow`	all versions	1.7.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for langflow-base. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update langflow-base to 0.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-21445 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 pinpoints whether CVE-2026-21445 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2026-21445. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to version 1.7.0.dev45, multiple critical API endpoints in Langflow are missing authentication controls. The issue allows any unauthenticated user to access sensitive user conversation data, transaction histories, and perform destructive operations including message deletion. This affects endpoints handling personal data and system operations that should require proper authorization. Version 1.7.0.dev45 contains a patch.

O3 Security · Impact-Aware SCA

Is CVE-2026-21445 in your dependencies?

O3 detects CVE-2026-21445 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

CVE-2026-21445