How severe is CVE-2017-18393?

CVE-2017-18393 has a CVSS 3.x base score of 2.7, rated low severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2017-18393 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-18393?

CVE-2017-18393 affects Cpanel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-18393?

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

When was CVE-2017-18393 published?

CVE-2017-18393 was published on 2019-08-02 and last updated on 2026-06-17.

CVE-2017-18393

CVE-2017-18393 is a low-severity vulnerability in Cpanel with a CVSS 3.x base score of 2.7. 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-20.

Key facts

Severity: Low (CVSS 3.x base score 2.7)
CVSS v2: 4.0
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cpanel
Published: 2019-08-02
Last modified: 2026-06-17

Description

cPanel before 68.0.15 does not block a username of postmaster, which might allow reception of private e-mail (SEC-326).

Frequently asked questions

What is CVE-2017-18393?: cPanel before 68.0.15 does not block a username of postmaster, which might allow reception of private e-mail (SEC-326).
How severe is CVE-2017-18393?: CVE-2017-18393 has a CVSS 3.x base score of 2.7, rated low severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2017-18393 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-18393?: CVE-2017-18393 affects Cpanel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-18393?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-18393 published?: CVE-2017-18393 was published on 2019-08-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:cpanel:cpanel:*:*:*:*:*:*:*:*

More vulnerabilities in Cpanel

CVE-2004-1770 — Critical (CVSS 10.0): The login page for cPanel 9.1.0, and possibly other versions, allows remote attackers to execute arbitrary code via…
CVE-2004-1769 — Critical (CVSS 10.0): The "Allow cPanel users to reset their password via email" feature in cPanel 9.1.0 build 34 and earlier, including 8.x,…
CVE-2003-1425 — Critical (CVSS 10.0): guestbook.cgi in cPanel 5.0 allows remote attackers to execute arbitrary commands via the template parameter.
CVE-2026-41940 — Critical (CVSS 9.8): cPanel and WHM versions after 11.40 contain an authentication bypass vulnerability in the login flow that allows…
CVE-2020-26108 — Critical (CVSS 9.8): cPanel before 88.0.13 mishandles file-extension dispatching, leading to code execution (SEC-488).
CVE-2020-26105 — Critical (CVSS 9.8): In cPanel before 88.0.3, insecure chkservd test credentials are used on a templated VM (SEC-554).

All CVEs affecting Cpanel →

Other CWE-20 (Improper Input Validation) vulnerabilities

CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…

Browse all CWE-20 (Improper Input Validation) vulnerabilities →