What is CVE-2021-42838?

CVE-2021-42838 is a medium-severity vulnerability in Grand Vice Info Co. Webopac7, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-11-15.

How severe is CVE-2021-42838?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Grand Vice Info Co. Webopac7

CVE-2021-42838

Grand Vice info Co. webopac7 book search field parameter does not properly restrict the input of special characters, thus unauthenticated attackers can inject JavaScript syntax remotely, and further perform reflective XSS attacks.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-11-15 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (48.2th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 48.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: +0.000

Affected products

Grand Vice Info Co. Webopac7 — versions 7.1.20160701, 1.8.20160701
Vice Webopac — versions 1.8.20160701, 7.1.20160701

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

www.twcert.org.tw/tw/cp-132-5286-b92c8-1.html (Third Party Advisory)

Frequently asked questions

What is CVE-2021-42838?: CVE-2021-42838 is a medium-severity vulnerability in Grand Vice Info Co. Webopac7, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-11-15.
How severe is CVE-2021-42838?: Medium severity. CVSS v3 base score is 6.1 out of 10.