Vulnerability · Published Jul 12, 2026 · Assigned by VulDB

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

Medium 6.3

In plain English

A medium-severity security flaw in Leantime. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 28% of all known vulnerabilities).

Severity (CVSS 3.1)6.3Medium

Exploit odds (30 days)0.3%top 71.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
n/a	Leantime	3.03.13.23.33.43.53.63.7

Weakness: CWE-285, CWE-266 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R

References

VDB-377838 | Leantime JSON-RPC Endpoint addUser improper authorization vdb-entry, technical-description
VDB-377838 | CTI Indicators (IOB, IOC, TTP, IOA) signature, permissions-required
CVE-2026-15509 | CVE Analysis and Report third-party-advisory
Submit #846167 | Leantime Leantime project management system 3.8.0 Privilege Escalation / Improper Authorization third-party-advisory
https://bytium.com/insights/leantime-priv-escalation-vulnerability-low-priv-to-owner exploit