#VU75999 Out-of-bounds write in ntp - CVE-2023-26552

Vulnerability identifier: #VU75999

Vulnerability risk: Medium

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-26552

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ntp
Server applications / Other server solutions

Vendor: ntp.org

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error within mstolfp in libntp/mstolfp.c. A remote attacker with control over a malicious NTP server can trick the victim into connecting to it, trigger an out-of-bounds write and execute arbitrary code on the target system via the client ntpq process.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

ntp: 4.2.8 - 4.2.8p15

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External links
https://github.com/spwpun/ntp-4.2.8p15-cves/blob/main/CVE-2023-26552
https://github.com/spwpun/ntp-4.2.8p15-cves/issues/1#issuecomment-1506667321

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.