CVE-2021-4097

mediumpriority · track · 22EPSS 0.009 · 59 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.87% (59th) EPSS

CVSS 5.8 · medium

Is it mine?

3 products

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-28

phpservermon is vulnerable to Improper Neutralization of CRLF Sequences

cvss

Technical severity, 0–10. One row per scoring source.

6.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 4.9

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.5

v3.06.3mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Lsecondary · ENISA EU

v3.06.3mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Lsecondary · security@huntr.devexploitability 2.8 · impact 3.4

v3.06.3mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Lsecondary · OSV

v3.15mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

The CWE weakness classes this flaw belongs to.

Products and version ranges known to be affected.

phpservermon phpservermon/phpservermonunspecified → 3.6.0enisa_euvdEU
phpservermonitor php server monitor< 3.6.0nvdUScpe:2.3:a:phpservermonitor:php_server_monitor:*:*:*:*:*:*:*:*
Packagist phpservermon/phpservermon≤ 3.5.2osvUSpkg:composer/phpservermon/phpservermon

Vendor and ecosystem advisories describing this.

GHSA-8qv8-fq5w-p966phpservermon is vulnerable to CRLF Injection2021-12-16ghsa · osvUS
phpservermon is vulnerable to Improper Neutralization of CRLF Sequences.

Other names and identifiers for this entity.

Which sources assert this record, and when.

published 2021-12-12modified 2026-06-17

External citations — patches, advisories, analysis.

scry

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