CVE-2026-23621Network attack vector

Authenticated directory enumeration via unrestricted path probe

Published Feb 19, 2026 · Updated Feb 19, 2026

Directory existence disclosure in GFI MailEssentials before 22.4 allows remote authenticated users to probe arbitrary server paths. The ListServer.IsPathExist() web method URL-decodes the JSON path value and passes it without restriction to Directory.Exists(), returning an observable result for any supplied directory. Access to the MailEssentials configuration interface is required; the oracle reveals whether directories exist but does not read files or list directory contents.

CVSS severity5.3
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Directory existence disclosure in GFI MailEssentials before 22.4 allows remote authenticated users to probe arbitrary server paths. The ListServer.IsPathExist() web method URL-decodes the JSON path value and passes it without restriction to Directory.Exists(), returning an observable result for any supplied directory. Access to the MailEssentials configuration interface is required; the oracle reveals whether directories exist but does not read files or list directory contents.

The record

CVE
CVE-2026-23621
Published
Feb 19, 2026
Updated
Feb 19, 2026
Vendor
GFI Software
Product
GFI MailEssentials
Classifications
CWE-203, T1083
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <22.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

GFI Software · GFI MailEssentialsversion=0 <22.4

Published CVSS scores

5.3VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
4.3VulnCheckCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-203Observable Discrepancy
T1083File and Directory Discovery

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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