CVE-2021-3831

MEDIUM 6.1CVE-2021-3831 · Published 14/12/2021 · updated 17/06/2026

In short

CVE-2021-3831 is a MEDIUM (CVSS 6.1) vulnerability affecting gnuboard5 (gnuboard).
Chance of exploitation in the next 30 days (EPSS): 1.8%, higher than 79.1% of all vulnerabilities.
Fix: update to 5.4.20 or later.

Package	Affected versions	Patched versions
gnuboard5 gnuboard	`< 5.4.20`	`5.4.20`

gnuboard5 is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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