CVE-2021-22873Public exploitNetwork attack vector

User redirection via attacker-controlled delivery parameters

Published Jan 21, 2021 · Updated Aug 3, 2024

Open redirect in Revive Adserver before 5.1.0 allows remote attackers to send users to untrusted sites through crafted delivery URLs. The public lg.php and ck.php scripts accept dest, oadest, or ct0 values and use them as redirect destinations instead of restricting redirects to banner properties. No account is required, but a user must open the crafted link; the resulting trusted-domain redirect can send that user to a phishing or other attacker-controlled site.

CVSS severity5.4
Medium
EPSS probability69.56%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Open redirect in Revive Adserver before 5.1.0 allows remote attackers to send users to untrusted sites through crafted delivery URLs. The public lg.php and ck.php scripts accept dest, oadest, or ct0 values and use them as redirect destinations instead of restricting redirects to banner properties. No account is required, but a user must open the crafted link; the resulting trusted-domain redirect can send that user to a phishing or other attacker-controlled site.

The record

CVE
CVE-2021-22873
Published
Jan 21, 2021
Updated
Aug 3, 2024
Vendor
Revive Adserver Project
Product
Revive Adserver
Classifications
CWE-601
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 21, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Fixed in 5.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Revive Adserver Project · Revive Adserverversion=Fixed in 5.1.0

Published CVSS scores

5.4Revive AdserverCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-601URL Redirection to Untrusted Site ('Open Redirect')

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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