CVE-2015-1799

What it is

The symmetric-key feature in the receive function in ntp_proto.c in ntpd in NTP 3.x and 4.x before 4.2.8p2 performs state-variable updates upon receiving certain invalid packets, which makes it easier for man-in-the-middle attackers to cause a denial of service (synchronization loss) by spoofing the source IP address of a peer.

At a glance

Exploitability

Can be exploited from the same network segment without logging in. Limited direct impact.

Exploit odds

0.9% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2015-04-08 10:59 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 00:23 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.9% in the next 30 days (EPSS).
• Severity: 4.3 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2015-04-08 10:59 UTC

Last modified

2026-06-17 00:23 UTC

Exploit probability

0.9% · EPSS, next 30 days

Weakness

CWE-17

Record status

Modified

Affected

• Ntp ≤ 4.2.7p444

Attack profile CVSS 2.0 · 4.3

Attack vector

Adjacent network

Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

Partial

Availability

Partial

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2015-1799.md and follow it. Check whether this project is affected by CVE-2015-1799. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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