CVE-2023-40764
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedUser enumeration is found in PHP Jabbers Car Rental Script v3.0. This issue occurs during password recovery, where a difference in messages could allow an attacker to determine if the user is valid or not, enabling a brute force attack with valid users.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidencePHP Jabbers Car Rental Script v3.0 contains a user enumeration vulnerability in its password recovery function. The application returns different error messages or responses for valid versus invalid usernames, allowing attackers to determine which accounts exist on the system. This information can then be used to launch targeted brute force attacks against valid user accounts.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data= 3.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Confirm PHP Jabbers Car Rental Script version 3.0 is installedLocate the installation directory and check version.php or any version file in the web root, or check the admin panel About section for the exact version numberAffected if The installed version is exactly 3.0 (no other versions are listed as affected)
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Locate the password recovery endpointAccess the login page and identify the 'Forgot Password' or password recovery link. Common paths include /index.php?controller=Forgot or /forgot-password.phpAffected if The password recovery functionality is accessible on the website
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Test password recovery with a known invalid usernameSubmit a password recovery request using a username or email that does not exist in the system. Note the exact error message, HTTP response code, and any delay in responseAffected if The application returns a specific error message indicating the username does not exist, or responds noticeably faster than with a valid account
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Test password recovery with a known valid usernameSubmit a password recovery request using a username or email that IS registered in the system. Note the exact error message, HTTP response code, and any delay in responseAffected if The application returns a different message or behaves differently (e.g., says email sent, or shows a success message) compared to the invalid username test
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Compare responses to detect user enumerationAnalyze both responses from steps 3 and 4. Check for differences in: error messages, HTTP status codes, response timing, or any indication that reveals account existenceAffected if The responses differ in a way that allows an external attacker to determine whether a specific username or email is registered on the system
Your environment is affected if you are running PHP Jabbers Car Rental Script version 3.0 AND the password recovery function returns distinguishable responses between valid and invalid usernames, allowing an attacker to enumerate existing accounts.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataModify the password recovery endpoint to return a uniform message (e.g., 'If an account with that email exists, a recovery link has been sent') regardless of whether the submitted username or email is valid, eliminating any observable difference in response.
- Consultation1.0 h
- Implementation2.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-40764 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2023-40764 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data