CVE-2019-11331
Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed...
Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed port number is not required, which makes it easier for remote attackers to conduct off-path attacks.
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
Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed port number is not required, which makes it easier for remote attackers to conduct off-path attacks.
- Record
CVE-2019-11331- 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 - CVSS 2.0
- 6.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:P - Updated
- 2026-11-02
CVE List No score
Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed port number is not required, which makes it easier for remote attackers to conduct off-path attacks.
- Record
CVE-2019-11331- Updated
- 2026-11-02
EUVDEUVD-2019-3012 No score
Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed port number is not required, which makes it easier for remote attackers to conduct off-path attacks.
- Record
EUVD-2019-3012- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-2c4g-qfqp-42mh
Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed...
Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed port number is not required, which makes it easier for remote attackers to conduct off-path attacks.
- Record
GHSA-2c4g-qfqp-42mh- 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
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-11331 is a high vulnerability (CVSS 8.1) in Ntp, published April 18, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.27%, the 83rd percentile. No source names a fixed version.
References
tools.ietf.org/html/draft-gont-ntp-port-randomization-00
securityfocus.com/bid/108010
support.f5.com/csp/article/K09940637
nvd.nist.gov/vuln/detail/CVE-2019-11331
github.com/advisories/GHSA-2c4g-qfqp-42mh