Which products and versions are affected by CVE-2020-35730?

Affected: Webmail (Roundcube); Debian Linux versions 9.0; Fedora (Fedoraproject) versions 32, 33, among others. The full list is in the CVE brief.

Is CVE-2020-35730 being exploited in the wild?

It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Jun 20, 2023.

Is CVE-2020-35730 in the CISA KEV catalog?

Yes. It was added on Jun 22, 2023 with a federal remediation due date of Jul 13, 2023.

Is there a public exploit for CVE-2020-35730?

Public exploit code is available.

Is there a fix for CVE-2020-35730?

Fixed versions are available, including roundcube 1.2.13, roundcube 1.2.3+dfsg.1-4+deb9u8, roundcube 1.2~beta+dfsg.1-0ubuntu1+esm2.

How urgently should CVE-2020-35730 be patched?

Brandefense priority: patch immediately, because it is listed as exploited in the wild.

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Vulnerability Intelligence

CVE-2020-35730

MediumExploitedPublic exploit

roundcube - security update

Published Dec 31, 2020 · Updated Sep 17, 2026 · Also known as BIT-roundcube-2020-35730, DEBIAN-CVE-2020-35730, DLA-2508-1, DSA-4821-1, TR-20-1053, UBUNTU-CVE-2020-35730

Key Facts

Patch immediately

CVE-2020-35730 is a medium-severity vulnerability (CVSS 6.1 v3.1) affecting Webmail (Roundcube), Debian Linux, Fedora (Fedoraproject) and 2 more products.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Jun 20, 2023. Public exploit code is available.
EPSS estimates a 33% probability of exploitation in the next 30 days.
Fixed versions are available, including roundcube 1.2.13, roundcube 1.2.3+dfsg.1-4+deb9u8, roundcube 1.2~beta+dfsg.1-0ubuntu1+esm2.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v3.1

6.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS (30-day exploit likelihood)

33%

Higher than 98.3% of all scored CVEs

Exploited in the wild

Yes

4 catalog listings

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2020-35730 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

An XSS issue was discovered in Roundcube Webmail before 1.2.13, 1.3.x before 1.3.16, and 1.4.x before 1.4.10. The attacker can send a plain text e-mail message, with JavaScript in a link reference element that is mishandled by linkref_addindex in rcube_string_replacer.php.

Known-Exploited Catalog Listings

Catalog	Added	Remediation due	Ransomware use
CISA KEV	Jun 22, 2023	Jul 13, 2023	Not reported
Industry KEV feed	Jun 20, 2023	Jul 13, 2023	Not reported
CIRCL KEV	Jun 22, 2023	Jul 13, 2023	Not reported
ENISA EUVD	Jun 22, 2023	n/a	Not reported

Required action: Apply updates per vendor instructions.

Affected Products

32 affected entries in total

Product	Affected versions	Fixed in
WebmailRoundcube	See advisory	1.2.13
Debian LinuxDebian	9.0	n/a
FedoraFedoraproject	32, 33	n/a
roundcubemailarch	See advisory	1.4.10-1
roundcubebitnami	See advisory	1.2.13

Patched Releases

roundcube

1.2.13, 1.2.3+dfsg.1-4+deb9u8, 1.2~beta+dfsg.1-0ubuntu1+esm2, 1.3.16, 1.3.16+dfsg.1-1~deb10u1, 1.3.6+dfsg.1-1ubuntu0.1~esm2, 1.4.10, 1.4.10+dfsg.1-1, 1.4.3+dfsg.1-1ubuntu0.1~esm2, 1.5.0+dfsg.1-2ubuntu0.1~esm1

Webmail

1.2.13

roundcubemail

1.3.16-bp151.4.6.1, 1.3.16-bp152.4.10.1, 1.3.16-bp152.4.14.1, 1.3.16-bp152.4.18.1, 1.3.16-bp152.4.6.1, 1.3.16-lp152.4.6.1, 1.4.10-1, 1.4.11-1.3, 1.5.3-bp154.2.3.1

Timeline

Publicly disclosed
Dec 31, 2020
Added to Industry KEV feed
Jun 20, 2023
Added to CISA KEV
Jun 22, 2023
Added to CIRCL KEV
Jun 22, 2023
Added to ENISA EUVD
Jun 22, 2023
Last updated
Sep 17, 2026

Weakness Type

CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

References

15 more references in the full CVE brief

FAQ

Common Questions.

An XSS issue was discovered in Roundcube Webmail before 1.2.13, 1.3.x before 1.3.16, and 1.4.x before 1.4.10.
Affected: Webmail (Roundcube); Debian Linux versions 9.0; Fedora (Fedoraproject) versions 32, 33, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Jun 20, 2023.
Yes. It was added on Jun 22, 2023 with a federal remediation due date of Jul 13, 2023.
Public exploit code is available.
Fixed versions are available, including roundcube 1.2.13, roundcube 1.2.3+dfsg.1-4+deb9u8, roundcube 1.2~beta+dfsg.1-0ubuntu1+esm2.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

Is CVE-2020-35730 Running On Your Attack Surface?

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