CVE-2024-39097Public exploitNetwork attack vector

Phishing redirects via double-slash login URLs

Published Aug 26, 2024 · Updated Jan 26, 2026

Open redirect in GNUBOARD6 6.0.4 and earlier allows remote attackers to send users to an untrusted site after login. The login URL validator accepts scheme-relative values beginning with // because it treats any leading slash as a local path, and the login handler passes the accepted value to RedirectResponse. Exploitation requires a user to follow a crafted login link and authenticate, after which the browser reaches the attacker-chosen host, enabling phishing.

CVSS severity6.1
Medium
EPSS probability0.39%
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 GNUBOARD6 6.0.4 and earlier allows remote attackers to send users to an untrusted site after login. The login URL validator accepts scheme-relative values beginning with // because it treats any leading slash as a local path, and the login handler passes the accepted value to RedirectResponse. Exploitation requires a user to follow a crafted login link and authenticate, after which the browser reaches the attacker-chosen host, enabling phishing.

The record

CVE
CVE-2024-39097
Published
Aug 26, 2024
Updated
Jan 26, 2026
Vendor
GNUBOARD
Product
GNUBOARD6
Classifications
CWE-601, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 26, 2024CVE publishedPublication date reported by the CVE source.
  2. Jan 26, 2026Record 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=0 <=6.0.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

GNUBOARD · GNUBOARD6version=0 <=6.0.4

Published CVSS scores

6.1CISA-ADPCVSS: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')
T1566.002Spearphishing Link

Public exploit references

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Technologies

Your stack

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Your stack

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