How severe is CVE-2023-40765?

CVE-2023-40765 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-40765 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-40765?

CVE-2023-40765 affects Phpjabbers Event Booking Calendar. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-40765?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2023-40765 published?

CVE-2023-40765 was published on 2023-08-28 and last updated on 2026-06-17.

CVE-2023-40765

CVE-2023-40765 is a critical-severity vulnerability in Phpjabbers Event Booking Calendar with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-209.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-209
Affected product: Phpjabbers Event Booking Calendar
Published: 2023-08-28
Last modified: 2026-06-17

Description

User enumeration is found in PHPJabbers Event Booking Calendar v4.0. 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.

Frequently asked questions

What is CVE-2023-40765?: User enumeration is found in PHPJabbers Event Booking Calendar v4.0. 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.
How severe is CVE-2023-40765?: CVE-2023-40765 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-40765 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-40765?: CVE-2023-40765 affects Phpjabbers Event Booking Calendar. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-40765?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-40765 published?: CVE-2023-40765 was published on 2023-08-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:phpjabbers:event_booking_calendar:4.0:*:*:*:*:*:*:*

More vulnerabilities in Phpjabbers Event Booking Calendar

CVE-2023-51293 — High (CVSS 7.5): A lack of rate limiting in the 'Forgot Password', 'Email Settings' feature of PHPJabbers Event Booking Calendar v4.0…
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CVE-2014-10014 — Medium (CVSS 6.8): Multiple cross-site request forgery (CSRF) vulnerabilities in PHPJabbers Event Booking Calendar 2.0 allow remote…
CVE-2023-51295 — Medium (CVSS 6.5): PHPJabbers Event Booking Calendar v4.0 is vulnerable to Multiple HTML Injection in the "name, plugin_sms_api_key,…
CVE-2023-51296 — Medium (CVSS 6.1): PHPJabbers Event Booking Calendar v4.0 is vulnerable to Cross-Site Scripting (XSS) in the "name, plugin_sms_api_key,…
CVE-2023-51298 — Medium (CVSS 4.7): PHPJabbers Event Booking Calendar v4.0 is vulnerable to CSV Injection vulnerability which allows an attacker to execute…

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