Incorrect authorization in Apache Pulsar - CVE-2026-105942
Published: October 23, 2026
Vulnerability identifier: #VU157386
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-105942
CWE-ID: CWE-863
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to escalate privileges by exercising permissions granted to a proxy rather than the original principal.
The vulnerability exists due to incorrect authorization in Apache Pulsar's broker and functions worker when authorizing the original principal of a proxied request using the proxy's authentication data. A remote user can submit requests through a proxy whose token grants elevated roles to perform operations beyond their own permissions when MultiRolesTokenAuthorizationProvider is used; custom authorization providers that use authentication data may be similarly affected.
Affected software
Apache Pulsar
How to mitigate CVE-2026-105942
Install security update from vendor's website.
Apache Pulsar - addressed in versions 4.0.14, 4.2.5