CVE-2026-35540
Detail
Description
An issue was discovered in Roundcube Webmail 1.6.0 before 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to SSRF or Information Disclosure, e.g., if stylesheet links point to local network hosts.
Metrics
NVD enrichment efforts reference publicly available information to associate
vector strings. CVSS information contributed by other sources is also
displayed.
CVSS 4.0 Severity and Vector Strings:
NVD assessment
not yet provided.
CVSS 3.x Severity and Vector Strings:
Vector:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
CVSS 2.0 Severity and Vector Strings:
Base
Score:
NVD assessment
not yet provided.
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Weakness Enumeration
| CWE-ID |
CWE Name |
Source |
|
CWE-669
|
Incorrect Resource Transfer Between Spheres |
MITRE
|
Change History
4 change records found show changes
CVE Modified by CISA-ADP
6/17/2026 6:40:44 AM
| Action |
Type |
Old Value |
New Value |
| Added |
SSVC |
{"timestamp":"2026-04-03T12:52:31.294531Z","id":"CVE-2026-35540","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}
|
CVE Modified by MITRE
6/17/2026 6:40:44 AM
| Action |
Type |
Old Value |
New Value |
| Added |
Affected |
[{"vendor":"Roundcube","product":"Webmail","defaultStatus":"unaffected","versions":[{"version":"1.6.0","lessThan":"1.6.14","versionType":"semver","status":"affected"}]}]
|
Initial Analysis by NIST
4/07/2026 4:52:15 PM
| Action |
Type |
Old Value |
New Value |
| Added |
CVSS V3.1 |
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
|
| Added |
CPE Configuration |
OR
*cpe:2.3:a:roundcube:webmail:*:*:*:*:*:*:*:* versions from (including) 1.6.0 up to (excluding) 1.6.14
|
| Added |
Reference Type |
MITRE: https://github.com/roundcube/roundcubemail/commit/27ec6cc9cb25e1ef8b4d4ef39ce76d619caa6870 Types: Patch
|
| Added |
Reference Type |
MITRE: https://github.com/roundcube/roundcubemail/commit/579b68eff90650a5c782e153debd66c765648942 Types: Patch
|
| Added |
Reference Type |
MITRE: https://github.com/roundcube/roundcubemail/releases/tag/1.6.14 Types: Release Notes
|
| Added |
Reference Type |
MITRE: https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5 Types: Release Notes
|
| Added |
Reference Type |
MITRE: https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14 Types: Vendor Advisory
|
New CVE Received from MITRE
4/03/2026 1:16:22 AM
| Action |
Type |
Old Value |
New Value |
| Added |
Description |
An issue was discovered in Roundcube Webmail 1.6.0 before 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to SSRF or Information Disclosure, e.g., if stylesheet links point to local network hosts.
|
| Added |
CVSS V3.1 |
AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
|
| Added |
CWE |
CWE-669
|
| Added |
Reference |
https://github.com/roundcube/roundcubemail/commit/27ec6cc9cb25e1ef8b4d4ef39ce76d619caa6870
|
| Added |
Reference |
https://github.com/roundcube/roundcubemail/commit/579b68eff90650a5c782e153debd66c765648942
|
| Added |
Reference |
https://github.com/roundcube/roundcubemail/releases/tag/1.6.14
|
| Added |
Reference |
https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5
|
| Added |
Reference |
https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14
|
Quick Info
CVE Dictionary Entry: CVE-2026-35540 NVD
Published Date: 04/03/2026 NVD
Last Modified: 06/17/2026
Source: MITRE
|
