SmarterTools SmarterMail up to 100.0.9609 Attachment Download Endpoint weak prng

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in SmarterTools SmarterMail up to 100.0.9609. Affected by this vulnerability is an unknown functionality of the component Attachment Download Endpoint. Such manipulation leads to weak prng. This vulnerability is referenced as CVE-2026-40514. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in SmarterTools SmarterMail up to 100.0.9609. It has been rated as problematic. Affected by this issue is an unknown part of the component Attachment Download Endpoint. The manipulation with an unknown input leads to a weak prng vulnerability. Using CWE to declare the problem leads to CWE-338. The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG's algorithm is not cryptographically strong. Impacted is confidentiality. CVE summarizes:

SmarterTools SmarterMail builds prior to 9610 contain a cryptographic weakness in the file and email sharing endpoints that use DES-CBC encryption with keys and initialization vectors derived from System.Random seeded with insufficient entropy, reducing the seed space to approximately 19,000 possible values. An unauthenticated attacker can use the attachment download endpoint as an oracle to determine the seed in use and derive encryption keys and initialization vectors to forge sharing tokens for arbitrary emails, attachments, or file storage contents without prior access to the targeted content.

The weakness was published by Maximilian Wiegand. The advisory is available at smartertools.com. This vulnerability is handled as CVE-2026-40514 since 04/13/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1600.001 by the MITRE ATT&CK project.

Upgrading to version 100.0.9610 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.2

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 9.1
NVD Vector: 🔒

CNA Base Score: 5.9
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Weak prng
CWE: CWE-338 / CWE-331 / CWE-330
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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: SmarterMail 100.0.9610

Timelineinfo

04/13/2026 CVE reserved
04/27/2026 +14 days Advisory disclosed
04/27/2026 +0 days VulDB entry created
06/04/2026 +38 days VulDB entry last update

Sourcesinfo

Advisory: smartertools.com
Researcher: Maximilian Wiegand
Status: Confirmed

CVE: CVE-2026-40514 (🔒)
GCVE (CVE): GCVE-0-2026-40514
GCVE (VulDB): GCVE-100-359810

Entryinfo

Created: 04/27/2026 17:12
Updated: 06/04/2026 18:27
Changes: 04/27/2026 17:12 (77), 06/04/2026 18:27 (11)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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