How severe is CVE-2020-21493?

CVE-2020-21493 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2020-21493 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-21493?

CVE-2020-21493 affects Xiuno Xiunobbs. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-21493?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-21493 published?

CVE-2020-21493 was published on 2021-10-04 and last updated on 2026-06-17.

CVE-2020-21493

CVE-2020-21493 is a medium-severity vulnerability in Xiuno Xiunobbs with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Xiuno Xiunobbs
Published: 2021-10-04
Last modified: 2026-06-17

Description

An issue in the component route\user.php of Xiuno BBS v4.0.4 allows attackers to enumerate usernames.

Frequently asked questions

What is CVE-2020-21493?: An issue in the component route\user.php of Xiuno BBS v4.0.4 allows attackers to enumerate usernames.
How severe is CVE-2020-21493?: CVE-2020-21493 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2020-21493 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-21493?: CVE-2020-21493 affects Xiuno Xiunobbs. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-21493?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-21493 published?: CVE-2020-21493 was published on 2021-10-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:xiuno:xiunobbs:4.0.4:*:*:*:*:*:*:*

More vulnerabilities in Xiuno Xiunobbs

CVE-2019-19998 — High (CVSS 7.5): Xiuno BBS 4.0 allows XXE via plugin/xn_wechat_public/route/token.php.
CVE-2020-19914 — Medium (CVSS 6.1): Cross Site Scripting (XSS) in xiunobbs 4.0.4 allows remote attackers to execute arbitrary web script or HTML via the…
CVE-2020-21496 — Medium (CVSS 6.1): A cross-site scripting (XSS) vulnerability in the component /admin/?setting-base.htm of Xiuno BBS 4.0.4 allows…
CVE-2020-21495 — Medium (CVSS 6.1): A cross-site scripting (XSS) vulnerability in the component /admin/?setting-base.htm of Xiuno BBS 4.0.4 allows…
CVE-2020-21494 — Medium (CVSS 6.1): A cross-site scripting (XSS) vulnerability in the component install\install.sql of Xiuno BBS 4.0.4 allows attackers to…
CVE-2018-15559 — Medium (CVSS 6.1): The editor in Xiuno BBS 4.0.4 allows stored XSS.

All CVEs affecting Xiuno Xiunobbs →