CVE-2021-24406Public exploitNetwork attack vector

Credential phishing via unvalidated post-login redirect

Published Jul 6, 2021 · Updated Aug 3, 2024

Open redirect in wpForo Forum before 1.9.7 allows remote attackers to send users to an attacker-controlled site after forum login. The forum login handler accepts the redirect_to parameter as an external destination without validating it before issuing the post-login redirect. Exploitation requires a user to follow a crafted login URL and authenticate; the redirect can support credential phishing but does not itself disclose credentials.

CVSS severity6.1
Medium
EPSS probability2.92%
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 wpForo Forum before 1.9.7 allows remote attackers to send users to an attacker-controlled site after forum login. The forum login handler accepts the redirect_to parameter as an external destination without validating it before issuing the post-login redirect. Exploitation requires a user to follow a crafted login URL and authenticate; the redirect can support credential phishing but does not itself disclose credentials.

The record

CVE
CVE-2021-24406
Published
Jul 6, 2021
Updated
Aug 3, 2024
Vendor
AdvancedCoding
Product
wpForo Forum
Classifications
CWE-601, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 6, 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

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=1.9.7 <1.9.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

AdvancedCoding · wpForo Forumversion=1.9.7 <1.9.7

Published CVSS scores

5.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:N
6.1WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
6.1NIST NVDCVSS: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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')
T1566.002Spearphishing Link

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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