TI-2023-16369 Aliases CVE-2023-33192 GHSA-qwhm-h7v3-mrjx

Improper handling of NTS cookie length that could crash the ntpd-rs server

MEDIUM 40CWE-130Published 2023-05-27 · Updated 2025-01-14

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

ntpd-rs is an NTP implementation written in Rust. ntpd-rs does not validate the length of NTS cookies in received NTP packets to the server. An attacker can crash the server by sending a specially crafted NTP packet containing a cookie shorter than what the server expects. The server also crashes when it is not configured to handle NTS packets. The issue was caused by improper slice indexing. The indexing operations were replaced by safer alternatives that do not crash the ntpd-rs server process but instead properly handle the error condition. A patch was released in version 0.3.3.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00708 53rd percentileScored 2026-11-07

Fix Fixed ntpd-rs (pendulum-project): 0.3.3ntpd (crates.io): 0.3.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
pendulum-project	ntpd-rs	0.3.0 to before 0.3.3	0.3.3	Patch available	CNA
—	ntpd (crates.io)	0.3.0 to before 0.3.3	0.3.3	Patch available	GHSA-qwhm-h7v3-mrjx

ntpd-rs Vendorpendulum-project Affected 0.3.0 to before 0.3.3 Fixed in 0.3.3 Patch available CNA
ntpd (crates.io) Vendor— Affected 0.3.0 to before 0.3.3 Fixed in 0.3.3 Patch available GHSA-qwhm-h7v3-mrjx

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:tweedegolf:ntpd-rs::::::rust::*	0.3.0 to before 0.3.3	Vulnerable	Tweedegolf

cpe:2.3:a:tweedegolf:ntpd-rs:*:*:*:*:*:rust:*:* Versions 0.3.0 to before 0.3.3 Vulnerable ·Tweedegolf

Remediation

Fix · CNA ntpd-rs (pendulum-project) Fixed in 0.3.3
Fix · GHSA-qwhm-h7v3-mrjx ntpd (crates.io) Fixed in 0.3.3 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2023-33192
2026-10-03 Alias added: GHSA-qwhm-h7v3-mrjx

References

Patch 1

https://github.com/pendulum-project/ntpd-rs/pull/752

Advisory 2

Other 2

TI-2024-25763 Unlimited number of NTS-KE connections can crash ntpd-rs server CVSS 3.1HIGH 7.5
TI-2025-35909 DoS Vulnerability in ntpd-rs CVSS 3.1MEDIUM 5.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences