CVE-2026-55255
Exploitation confirmed. First attested on 2026-07-07 by CISA-ADP, CISA KEV, GCVE · kevintel.
- Published2026-06-23
- Fixed in1.9.2 · 1.9.1
- WeaknessCWE-639
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, an Insecure Direct Object Reference (IDOR) vulnerability in /api/v1/responses endpoint allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request. This vulnerability is fixed in 1.9.1.
Timeline
dates in UTCObserved activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-55255?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-55255?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
OSV · NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 1.9 | < 1.9.2 | 1.9.2 | OSV |
| 1.9 | < 1.9.1 | 1.9.1 | NVD · OSV |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Langflow to 1.9.2 · 1.9.1
- CISA’s required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.due 2026-07-10
Advisories and patches
- github.comPatch
- github.comPatch
- github.comMitigation · Vendor Advisory
Detection
read 2026-10-23 19:25 UTC- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- 1 repository, unverifiedrootdirective-sec/CVE-2026-55255-Lab PoC-in-GitHub
CISA Known Exploited Vulnerability
- Date Added
- 2026-07-07
- Patch Due Date
- 2026-07-10
- Ransomware Use
- Unknown
- Required Action
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Sources
- NVDCVE recordread 2026-10-23
- CISA KEVKEV entry2026-07-07
- GCVEexploitation2026-07-07
- CISA-ADPSSVC decisionactive2026-07-08
- OpenCVESSVC decisionactive—
- CNACVSS 3.18.4read 2026-10-23
- CNAweakness (CWE)CWE-639read 2026-10-23
- FIRST EPSSEPSS score0.9 %2026-10-23
- PoC-in-GitHubproof of concept1read 2026-10-23
- OSVaffected packages—
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:L
- Published
- 2026-06-23
- Last Modified
- 2026-10-07
- NVD status
- Analyzed
Frequently asked questions
What is CVE-2026-55255?
Is CVE-2026-55255 actively exploited?
What is the CVSS score for CVE-2026-55255?
Running langflow? Hear about its next vulnerability
Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.