What is CVE-2021-22872?

CVE-2021-22872 is a medium-severity vulnerability in Revive-Adserver Revive Adserver, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-01-26.

How severe is CVE-2021-22872?

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

Is CVE-2021-22872 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XSS in Revive-Adserver Revive Adserver

CVE-2021-22872

Revive Adserver before 5.1.0 is vulnerable to a reflected cross-site scripting (XSS) vulnerability via the publicly accessible afr.php delivery script. While this issue was previously addressed in modern browsers as CVE-2020-8115, some older browsers (e.g., IE10) that do not automatically URL encode parameters were still vulnerable.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-01-26 · 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: 0.034 (88.6th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 88.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.034 · newest: 0.034 · change: 0.000

Affected products

Revive-Adserver Revive Adserver
Https://github.com/revive-Adserver/revive-Adserver — versions Fixed in 5.1.0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

References

www.revive-adserver.com/security/revive-sa-2021-001/ (Vendor Advisory)
hackerone.com/reports/986365 (Exploit, Third Party Advisory)
github.com/revive-adserver/revive-adserver/commit/00fdb8d0e (Patch, Third Party Advisory)
github.com/revive-adserver/revive-adserver/commit/1dbcf7d50 (Patch, Third Party Advisory)
seclists.org/fulldisclosure/2021/Jan/60 (mailing-list, Mailing List, Third Party Advisory, Broken Link)
packetstormsecurity.com/files/161070/Revive-Adserver-5.0.5-Cross-Site-Scripting… (VDB Entry, Third Party Advisory)

Frequently asked questions

What is CVE-2021-22872?: CVE-2021-22872 is a medium-severity vulnerability in Revive-Adserver Revive Adserver, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-01-26.
How severe is CVE-2021-22872?: Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2021-22872 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.