CVE-2026-108558

MEDIUM
Published Nov 11, 2026 Modified Nov 12, 2026 CWE-79

Description

A reflected cross-site scripting vulnerability in the conversion-statistics pages of Revive Adserver 6.0.8 and earlier allows an unauthenticated attacker to execute JavaScript in an authenticated user's browser by persuading them to visit a crafted URL. An incorrect ownership check validates the advertiser identifier instead of the supplied website identifier, allowing malicious website input to reach HTML output without appropriate encoding. A related output issue affects the hour parameter. The issue is fixed in Revive Adserver 6.0.9 by validating the correct website identifier and normalising the hour parameter before formatting.

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CVSS v3.1 Score

6.1
MEDIUM
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0026
Probability of exploitation
0.18%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

References

Frequently Asked Questions

What is CVE-2026-108558? +
A reflected cross-site scripting vulnerability in the conversion-statistics pages of Revive Adserver 6.0.8 and earlier allows an unauthenticated attacker to execute JavaScript in an authenticated user's browser by persuading them to visit a crafted URL. An incorrect ownership check validates the advertiser identifier instead of the supplied website identifier, allowing malicious website input to reach HTML output without appropriate encoding. A related output issue affects the hour parameter. The issue is fixed in Revive Adserver 6.0.9 by validating the correct website identifier and normalising the hour parameter before formatting. It has a CVSS v3.1 base score of 6.1 (MEDIUM).
How severe is CVE-2026-108558? +
CVE-2026-108558 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0026, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-108558? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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