Skip to main content
HIGH

CVE-2023-27533

CVSS v3

8.8

HIGH

EPSS Score

2.0 %

exploit probability, as of 2026-09-25

CISA KEV

No

known exploited

Exploitation

—

SSVC status

Description

A vulnerability in input validation exists in curl <8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during server negotiation. The lack of proper input scrubbing allows an attacker to send content or perform option negotiation without the application's intent. This vulnerability could be exploited if an application allows user input, thereby enabling attackers to execute arbitrary code on the system.

Technical details

Published
2023-03-30

Frequently asked questions

What is CVE-2023-27533?

A vulnerability in input validation exists in curl <8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during server negotiation. The lack of proper input scrubbing allows an attacker to send content or perform option negotiation without the application's intent. This vulnerability could be exploited if an application allows user input, thereby enabling attackers to execute arbitrary code on the system.

Is CVE-2023-27533 actively exploited?

Active exploitation of CVE-2023-27533 has not been confirmed. Its EPSS score was 2.0% on 2026-09-25, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2023-27533?

CVE-2023-27533 has a CVSS v3 base score of 8.8 (HIGH severity).

Is CVE-2023-27533 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.

No credit card required · 500 free checks/month · Free API key