CVE-2023-38998Public exploitNetwork attack vector

Post-login phishing redirect via triple-slash URL

Published Aug 9, 2023 · Updated Oct 10, 2024

Open redirect in OPNsense Community Edition before 23.7 and Business Edition before 23.4.2 allows remote attackers to redirect users via crafted URLs. After a successful login, authgui.inc passes the url query parameter to the Location header; triple-slash values evade its host check. A victim must follow the crafted link and authenticate, after which the redirect can send the browser to an attacker-controlled site for phishing.

CVSS severity4.3
Medium
EPSS probability0.59%
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 OPNsense Community Edition before 23.7 and Business Edition before 23.4.2 allows remote attackers to redirect users via crafted URLs. After a successful login, authgui.inc passes the url query parameter to the Location header; triple-slash values evade its host check. A victim must follow the crafted link and authenticate, after which the redirect can send the browser to an attacker-controlled site for phishing.

The record

CVE
CVE-2023-38998
Published
Aug 9, 2023
Updated
Oct 10, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-601, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 9, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 10, 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?

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

4.3LogicalTrustCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/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

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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