Description
Zabbix through 4.4.0alpha1 allows User Enumeration. With login requests, it is possible to enumerate application usernames based on the variability of server responses (e.g., the "Login name or password is incorrect" and "No permissions for system access" messages, or just blocking for a number of seconds). This affects both api_jsonrpc.php and index.php.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | zabbix | 1:5.0.7+dfsg-1 | — |
| Debian 13 | zabbix | 1:5.0.7+dfsg-1 | — |
| Debian 12 | zabbix | 1:5.0.7+dfsg-1 | — |
| Debian 10 | zabbix | 1:4.0.4+dfsg-1+deb10u1 | DLA-3390-1 |
| Debian 9 | zabbix | 1:3.0.32+dfsg-0+deb9u1 | DLA-2631-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | zabbix | 1:4.0.17+dfsg-1ubuntu0.1~esm1 | USN-4767-1 |
| Ubuntu Pro 18.04 LTS | zabbix | 1:3.0.12+dfsg-1ubuntu0.1~esm3 | USN-4767-1 |
| Ubuntu Pro 16.04 LTS | zabbix | 1:2.4.7+dfsg-2ubuntu2.1+esm3 | USN-4767-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | zabbix | 1:2.2.2+dfsg-1ubuntu1+esm4 | USN-4767-1 |
Advisories 3
- USN-4767-1 zabbix vulnerabilities Ubuntu Security Notices (USN) · Jun 29, 2026
- DLA-3390-1 zabbix - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2631-1 zabbix - security update Debian Security (DSA / DLA) · Mar 9, 2026