What is CVE-2026-54432?
Roundcube Webmail before 1.6.17 and 1.7.x before 1.7.2 allows Stored Cross-Site Scripting (XSS). The issue occurs because the attachment MIME type is not properly escaped on the attachment-validation warning page.
The record classifies CVE-2026-54432 under weakness class CWE-79. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 106 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 4.7 — MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS (FIRST)
- 0.2% probability of exploitation in the next 30 days, higher than 9.7% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 2.7/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-07-14, last modified 2026-07-15
Is CVE-2026-54432 being exploited?
It currently carries a trending score of 15 in the Threadlinqs vulnerability feed.
Affected products and versions
- Roundcube: Webmail
How to fix CVE-2026-54432
No vendor patch reference has been recorded for CVE-2026-54432 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-54432
1 tracked threat in the Threadlinqs corpus references CVE-2026-54432, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on .