CVE-1999-1357: Netscape Communicator

High severity, CVSS 7.5. EPSS: 2% chance of exploitation in the next 30 days.

Netscape Communicator 4.04 through 4.7 (and possibly other versions) in various UNIX operating systems converts the 0x8b character to a "<" sign, and the 0x9b character to a ">" sign, which could allow remote attackers to attack other clients via cross-site scripting (CSS) in CGI programs that do not filter these characters.

Affected products

• Netscape Communicator: up to and including 4.7; version 4.04 only; version 4.51 only

Published 1999-10-05. Last modified 2026-06-16.