IBM Langflow OSS: Remote code execution via incomplete code security scanner blocklist
Summary
Langflow OSS versions 1.0.0 through 1.12.2 contain an incomplete blocklist in the code security scanner. An attacker who can reach the service may be able to execute arbitrary code on the server. According to the vendor's CVSS vector, the attacker needs low privileges, such as a user account, and no user interaction is required.
Affected
- IBM Langflow OSS 1.0.0 through 1.12.2
Fixed in
- Upgrade to Langflow OSS 1.12.3 or later
Workaround
- No workaround documented by IBM. Unknown.
- Until the upgrade, keep Langflow off the public internet and limit who can create or edit flows (general hardening, not an IBM workaround).
Exploitation
- No evidence of active exploitation, public exploits or confirmed compromises reported by IBM.
- Not listed in CISA KEV according to OpenCVE; the CISA KEV list was not checked directly.
- CISA SSVC: Exploitation none, Automatable no, Technical Impact total.
Our recommendation
- Check whether Langflow OSS is in use and which version is running.
- Upgrade to 1.12.3 or later, and patch the other vulnerabilities in IBM's bulletin in the same update.
- Restrict sign-up and flow-editing rights and check exposure to the internet.
- After patching, rotate API keys, database credentials and other secrets stored in Langflow.
- Monitor logs for unusual code execution or file access.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- IBM Security Bulletin: Langflow OSS www.ibm.com
- OSV: CVE-2026-97655 osv.dev
- GBHackers: IBM patches multiple Langflow OSS flaws gbhackers.com
- Cyberpress: IBM patches critical Langflow vulnerabilities cyberpress.org
- SecurityOnline: Langflow vulnerabilities in 1.12.3 securityonline.info
- VulDB: CVE-2026-97655 vuldb.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 21:31.
Original description (NVD)
IBM Langflow OSS 1.0.0 through 1.12.2 could allow a remote attacker to execute arbitrary code due to an incomplete blocklist in the code security scanner.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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