CVE-2024-37656Public exploitNetwork attack vector

Open redirect via unfiltered URL backslash

Published Jul 7, 2025 · Updated Jul 8, 2025

Open redirect in Gnuboard5 5.5.16 allows remote attackers to send users to attacker-controlled sites through a crafted logout URL. The bbs/logout.php handler fails to reject a backslash in the url parameter, so a backslash-prefixed host is treated as an external destination. Exploitation requires a user to follow the crafted link and enables phishing or exposure of information entered at the redirected site.

CVSS severity6.1
Medium
EPSS probability0.49%
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 Gnuboard5 5.5.16 allows remote attackers to send users to attacker-controlled sites through a crafted logout URL. The bbs/logout.php handler fails to reject a backslash in the url parameter, so a backslash-prefixed host is treated as an external destination. Exploitation requires a user to follow the crafted link and enables phishing or exposure of information entered at the redirected site.

The record

CVE
CVE-2024-37656
Published
Jul 7, 2025
Updated
Jul 8, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-601, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 7, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 8, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 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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