Roundcube Webmail up to 1.6.17/1.7.2 managesieve plugin input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.2$0-$5k0.21

Summaryinfo

A vulnerability was found in Roundcube Webmail up to 1.6.17/1.7.2. It has been rated as problematic. This impacts an unknown function of the component managesieve plugin. This manipulation causes input validation. The identification of this vulnerability is CVE-2026-75004. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability has been found in Roundcube Webmail up to 1.6.17/1.7.2 and classified as problematic. Affected by this vulnerability is an unknown function of the component managesieve plugin. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect integrity. The summary by CVE is:

In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, improper rule name quoting could lead to managesieve_disabled_actions setting bypass via a crafted rule name in a Sieve script. This issue only affects Roundcube instances using the managesieve plugin.

It is possible to read the advisory at roundcube.net. This vulnerability is known as CVE-2026-75004 since 08/17/2026. The exploitation appears to be easy. The attack can be launched remotely. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 1.6.18 or 1.7.3 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.3
CNA Vector (MITRE): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Webmail 1.6.18/1.7.3

Timelineinfo

08/17/2026 Advisory disclosed
08/17/2026 +0 days CVE reserved
08/17/2026 +0 days VulDB entry created
08/17/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: roundcube.net
Status: Confirmed

CVE: CVE-2026-75004 (🔒)
GCVE (CVE): GCVE-0-2026-75004
GCVE (VulDB): GCVE-100-391279

Entryinfo

Created: 08/17/2026 15:28
Changes: 08/17/2026 15:28 (64)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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