CVE-2018-12520
An issue was discovered in ntopng 3.4 before 3.4.180617. The PRNG involved in the generation of...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
8.1
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.
- Record
CVE-2018-12520- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 6.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:P - Weakness
- CWE-335
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2018-12520- Updated
- 2026-11-02
EUVDEUVD-2018-4490 No score
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.
- Record
EUVD-2018-4490- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-mx87-47cg-9wpg
8.1
An issue was discovered in ntopng 3.4 before 3.4.180617. The PRNG involved in the generation of...
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.
- Record
GHSA-mx87-47cg-9wpg- CVSS 3.0
- 8.1 High
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-335
- Updated
- 2026-11-02
OSV
8.1
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.
- Record
CVE-2018-12520- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2018-12520
8.1
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.
- Record
UBUNTU-CVE-2018-12520- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 3.0
- 8.1 High
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUSN-4842-1 No score
ntopng vulnerability
It was discovered that ntopng did not properly seed its random number generator, leading to predictable session tokens. An attacker could use this vulnerability to hijack a user's session.
- Record
USN-4842-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
ntopngUbuntu:Pro:16.04:LTS |
before 2.2+dfsg1-1ubuntu0.1~esm2, plus listed versions 1.2.1+dfsg1-2ubuntu12.0+dfsg1-12.2+dfsg1-12.2+dfsg1-1build1 |
2.2+dfsg1-1ubuntu0.1~esm2 |
ntopngUbuntu:Pro:18.04:LTS |
before 3.2+dfsg1-1ubuntu0.1~esm2, plus listed versions 2.4+dfsg1-32.4+dfsg1-43.2+dfsg1-1 |
3.2+dfsg1-1ubuntu0.1~esm2 |
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Exploit-DB | ntop-ng < 3.4.180617 - Authentication Bypass | 2018-07-03 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, Exploit-DB, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-12520 is a high vulnerability (CVSS 8.1) in Ntop Ntopng, published July 5, 2018. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 10.5%, the 95th percentile. Fixed in ntopng 2.2+dfsg1-1ubuntu0.1~esm2.
References
github.com/ntop/ntopng/commit/30610bda60cbfc058f90a1c0a17d0e8f4516221a
exploit-db.com/exploits/44973
seclists.org/fulldisclosure/2018/Jul/14
gist.github.com/Psychotropos/3e8c047cada9b1fb716e6a014a428b7f
nvd.nist.gov/vuln/detail/CVE-2018-12520
github.com/advisories/GHSA-mx87-47cg-9wpg
ubuntu.com/security/CVE-2018-12520
ubuntu.com/security/notices/USN-4842-1
cve.org/CVERecord?id=CVE-2018-12520