Network Time Protocol Version 4: Port Randomization

Metadata

Publisher: IETF
Doc Type: Standard
Pages: 9
Abstract: The Network Time Protocol (NTP) can operate in several modes. Some of these modes are based on the receipt of unsolicited packets and therefore require the use of a well-known port as the local port. However, in the case of NTP modes where the use of a well-known port is not required, employing such a well-known port unnecessarily facilitates the ability of attackers to perform blind/off-path attacks. This document formally updates RFC 5905, recommending the use of transport-protocol ephemeral port randomization for those modes where use of the NTP well-known port is not required.
Publication Date: 2021-08-01
Status Note: Proposed Standard
DOI: 10.17487/RFC9109
Link: https://doi.org/10.17487/RFC9109
Author(s): Fernando Gont
Guillermo Gont
Miroslav Lichvar
Keyword(s): Security

Latest version of IETF RFC 9109

Document Versions — IETF RFC 9109

▶ IETF RFC 9109 (2021-08-01)

THIS DOC [ACTIVE] [LATEST VERSION]

Normative Reference(s)

IETF RFC 2119 [Active*]
IETF RFC 5905 [Active*]
RFC6056 — RFC6056 EXTERNAL
IETF RFC 8174 [Active*]

Bibliographic Reference(s)

10.1007-978-3-319-70972-7_23 — NTP-security EXTERNAL
10.6028-jres.121.003 — NIST-NTP EXTERNAL
10.14722-ndss.2016.23090 — NTP-FRAG EXTERNAL
10.33012-2017.14978 — NTP-CHLNG EXTERNAL
IETF.draft-ietf-ntp-data-minimization-04 — I-D.ietf-ntp-data-minimization EXTERNAL
IETF.draft-irtf-pearg-numeric-ids-generation-07 — I-D.irtf-pearg-numeric-ids-generation EXTERNAL
The MITRE Corporation, "CVE-2019-1133", National Vulnerability Database, August 2020, <https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-11331>. EXTERNAL
"Network Time Foundation", <http://support.ntp.org/bin/view/Main/SecurityNotice>. EXTERNAL
IETF RFC 792 [Active*]
IETF RFC 2663 [Active*]
IETF RFC 3715 [Active*]
IETF RFC 4443 [Active*]
RFC4953 — RFC4953 EXTERNAL
IETF RFC 5927 [Active*]
IETF RFC 6335 [Active*]

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IETF RFC 9109, Network Time Protocol Version 4: Port Randomization
doi: 10.17487/RFC9109
url: https://doi.org/10.17487/RFC9109

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Referenced By

IETF RFC 9769 [Active*]