Description
An issue was discovered in ntopng 3.4 before 3.4.180617. The PRNG involved in the generation of session IDs is not seeded at program startup. This results in deterministic session IDs being allocated for active user sessions. An attacker with foreknowledge of the operating system and standard library in use by the host running the service and the username of the user whose session they're targeting can abuse the deterministic random number generation in order to hijack the user's session, thus escalating their access.
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.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | ntopng | 3.2+dfsg1-1ubuntu0.1~esm2 | USN-4842-1 |
| Ubuntu Pro 16.04 LTS | ntopng | 2.2+dfsg1-1ubuntu0.1~esm2 | USN-4842-1 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Exploit-DB 1
- ntop-ng < 3.4.180617 - Authentication Bypass EDB-44973 · webapps · Jul 3, 2018
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 1
- USN-4842-1 ntopng vulnerability Ubuntu Security Notices (USN) · Jun 25, 2026