Review reviewCritical

CVE-2026-54433

Roundcube Webmail, webmail

In Roundcube Webmail before 1.6.17 and 1.7.x before 1.7.2, there is Stored Cross-Site Scripting (XSS) via a crafted plain-text email message. The attacker-controlled JavaScript executes within the victim's authenticated session simply by opening or previewing the message (zero-click).

CVSS
10
EPSS
0.31%
23.6% percentile
CISA KEV
Not listed
Published
2026.07.15
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.31%
Technical severityCVSS 10

Vulnerability overview

In Roundcube Webmail before 1.6.17 and 1.7.x before 1.7.2, there is Stored Cross-Site Scripting (XSS) via a crafted plain-text email message. The attacker-controlled JavaScript executes within the victim's authenticated session simply by opening or previewing the message (zero-click).

Affected product and versions

Product
Roundcube Webmail, webmail
Affected versions
>= 1.6.0 < 1.6.17, >= 1.7.0 < 1.7.2, < 1.6.17
Fixed versions
1.6.17, 1.7.2

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Roundcube Webmail, webmail and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
CWE
CWE-79
CVE-2026-54433 — Roundcube Webmail, webmail | SECUFOCUS NOW