A reflected XSS vulnerability exists in multiple pages in version 22 of the Gibbon application that allows for arbitrary execution of JavaS…

published 2021-09-03 5y ago modified 2026-06-17 4mo ago also EUVD-2021-27669

cvss: 6.1; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.3%; EPSS 2.3% chance of exploitation in 30 days, percentile 83%
public exploits: 0; none known

A reflected XSS vulnerability exists in multiple pages in version 22 of the Gibbon application that allows for arbitrary execution of JavaScript (gibbonCourseClassID, gibbonPersonID, subpage, currentDate, or allStudents to index.php).

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Exploit prediction

2.32% chance of exploitation in the next 30 days, higher than 83% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

gibbonedu.org /
vendor-advisory
github.com /5qu1n7/CVE-2021-40492
third-party-advisory

Sources

CVE List CVE-2021-40492
NVD CVE-2021-40492

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