How severe is CVE-2018-18621?

CVE-2018-18621 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2018-18621 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-18621?

CVE-2018-18621 affects Communigate Communigate Pro. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-18621?

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

When was CVE-2018-18621 published?

CVE-2018-18621 was published on 2018-10-24 and last updated on 2026-06-17.

CVE-2018-18621

CVE-2018-18621 is a medium-severity vulnerability in Communigate Communigate Pro with a CVSS 3.x base score of 6.1. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Communigate Communigate Pro
Published: 2018-10-24
Last modified: 2026-06-17

Description

CommuniGate Pro 6.2 allows stored XSS via a message body in Pronto! Mail Composer, which is mishandled in /MIME/INBOX-MM-1/ if the raw email link (in .txt format) is modified and then renamed with a .html or .wssp extension.

Frequently asked questions

What is CVE-2018-18621?: CommuniGate Pro 6.2 allows stored XSS via a message body in Pronto! Mail Composer, which is mishandled in /MIME/INBOX-MM-1/ if the raw email link (in .txt format) is modified and then renamed with a .html or .wssp extension.
How severe is CVE-2018-18621?: CVE-2018-18621 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2018-18621 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-18621?: CVE-2018-18621 affects Communigate Communigate Pro. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-18621?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-18621 published?: CVE-2018-18621 was published on 2018-10-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:communigate:communigate_pro:6.2:*:*:*:*:*:*:*

More vulnerabilities in Communigate Communigate Pro

CVE-2017-16962 — Medium (CVSS 6.1): The WebMail components (Crystal, pronto, and pronto4) in CommuniGate Pro before 6.2.1 have stored XSS vulnerabilities…

All CVEs affecting Communigate Communigate Pro →

Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

CVE-2025-49410 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Imran Emu TC…
CVE-2024-47875 — Critical (CVSS 10.0): DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to…
CVE-2024-6886 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Gitea…
CVE-2023-45144 — Critical (CVSS 10.0): com.xwiki.identity-oauth:identity-oauth-ui is a package to aid in building identity and service providers based on…
CVE-2023-45138 — Critical (CVSS 10.0): Change Request is an pplication allowing users to request changes on a wiki without publishing the changes directly.…
CVE-2022-4361 — Critical (CVSS 10.0): Keycloak, an open-source identity and access management solution, has a cross-site scripting (XSS) vulnerability in the…

Browse all CWE-79 (Cross-site Scripting (XSS)) vulnerabilities →