CVE-2023-5631

Stored XSS vulnerability in Roundcube

Medium 6.1
Exploited: added to CISA KEV 26 Oct 2023

Description

Roundcube before 1.4.15, 1.5.x before 1.5.5, and 1.6.x before 1.6.4 allows stored XSS via an HTML e-mail message with a crafted SVG document because of program/lib/Roundcube/rcube_washtml.php behavior. This could allow a remote attacker to load arbitrary JavaScript code.

Key facts

Published: 18 Oct 2023
Last changed: 21 Oct 2025
Assigned by: ESET
KEV added: 26 Oct 2023
KEV fix due: 16 Nov 2023
EPSS: 76.337% likely to be exploited in the next 30 days, higher than 99.546% of CVEs (scores for 15 Nov 2026)
SSVC (CISA): Exploitation: active; Automatable: no; Technical impact: total

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

6.1CVSS 3.1, Mediumfrom the CNA (ESET)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

What to do

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.CISA KEV required action

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

CAPEC-592 Stored XSS (CNA impact statement)

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

Vendor	Product	Versions
Roundcube	Roundcubemail	Default status: unaffected 1.6.0 up to but excluding 1.6.3 (affected) 1.5.0 up to but excluding 1.5.4 (affected) 1.4.0 up to but excluding 1.5.14 (affected) 1.6.4 (unaffected) 1.5.5 (unaffected) 1.5.15 (unaffected)

Timeline

18 Oct 2023 Published
26 Oct 2023 CVE-2023-5631 added to CISA KEV
26 Oct 2023 Added to the CISA KEV catalogue

Weakness

CWE-79

Practice this bug class

HackZoneLabs has a hands-on lab on XSS (stored, reflected, DOM) (CWE-79).

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