How severe is CVE-2021-4240?

CVE-2021-4240 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over an adjacent network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-4240 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4240?

CVE-2021-4240 affects Phpservermonitor Php Server Monitor. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4240?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-4240 published?

CVE-2021-4240 was published on 2022-11-15 and last updated on 2026-06-17.

CVE-2021-4240

CVE-2021-4240 is a low-severity vulnerability in Phpservermonitor Php Server Monitor with a CVSS 3.x base score of 2.6. 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-330.

Key facts

Severity: Low (CVSS 3.x base score 2.6)
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-330
Affected product: Phpservermonitor Php Server Monitor
Published: 2022-11-15
Last modified: 2026-06-17

Description

A vulnerability, which was classified as problematic, was found in phpservermon. This affects the function generatePasswordResetToken of the file src/psm/Service/User.php. The manipulation leads to use of predictable algorithm in random number generator. The exploit has been disclosed to the public and may be used. The name of the patch is 3daa804d5f56c55b3ae13bfac368bb84ec632193. It is recommended to apply a patch to fix this issue. The identifier VDB-213717 was assigned to this vulnerability.

Frequently asked questions

What is CVE-2021-4240?: A vulnerability, which was classified as problematic, was found in phpservermon. This affects the function generatePasswordResetToken of the file src/psm/Service/User.php. The manipulation leads to use of predictable algorithm in random number generator. The exploit has been disclosed to the public and may be used. The name of the patch is 3daa804d5f56c55b3ae13bfac368bb84ec632193. It is recommended to apply a patch to fix this issue. The identifier VDB-213717 was assigned to this vulnerability.
How severe is CVE-2021-4240?: CVE-2021-4240 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over an adjacent network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-4240 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4240?: CVE-2021-4240 affects Phpservermonitor Php Server Monitor. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4240?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-4240 published?: CVE-2021-4240 was published on 2022-11-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:phpservermonitor:php_server_monitor:-:*:*:*:*:*:*:*

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