Postbox 7.0.65 on macOS com.apple.security.cs.disable-library-validation DYLD_INSERT_LIBRARIES default permission

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Postbox 7.0.65 on macOS. Affected by this vulnerability is an unknown functionality of the component com.apple.security.cs.disable-library-validation. Executing a manipulation of the argument DYLD_INSERT_LIBRARIES can lead to default permission. This vulnerability only affects products that are no longer supported by the maintainer. This vulnerability is registered as CVE-2025-5963. The attack needs to be launched locally. No exploit is available.

Detailsinfo

A vulnerability classified as critical was found in Postbox 7.0.65 on macOS. This vulnerability affects an unknown function of the component com.apple.security.cs.disable-library-validation. The manipulation of the argument DYLD_INSERT_LIBRARIES with an unknown input leads to a default permission vulnerability. The CWE definition for the vulnerability is CWE-276. During installation, installed file permissions are set to allow anyone to modify those files. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

The Postbox's configuration on macOS, specifically the presence of entitlements: "com.apple.security.cs.allow-dyld-environment-variables" and "com.apple.security.cs.disable-library-validation" allows for Dynamic Library (Dylib) injection. A local attacker with unprivileged access can use environment variables like DYLD_INSERT_LIBRARIES to successfully inject code in application's context and bypass Transparency, Consent, and Control (TCC). Acquired resource access is limited to previously granted permissions by the user. Access to other resources beyond granted-permissions requires user interaction with a system prompt asking for permission. The original company behind Postbox is no longer operational, the software will no longer receive updates. The acquiring company (em Client) did not cooperate in vulnerability disclosure.

The weakness was published with Karol Mazurek. The advisory is available at cert.pl. This vulnerability was named CVE-2025-5963 since 06/10/2025. The exploitation appears to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1222 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

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Version

Support

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: 5.3
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Default permission
CWE: CWE-276 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

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: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/10/2025 CVE reserved
06/20/2025 +10 days Advisory disclosed
06/20/2025 +0 days VulDB entry created
06/24/2025 +4 days VulDB entry last update

Sourcesinfo

Advisory: cert.pl
Organization: Karol Mazurek
Status: Not defined

CVE: CVE-2025-5963 (🔒)
GCVE (CVE): GCVE-0-2025-5963
GCVE (VulDB): GCVE-100-313390

Entryinfo

Created: 06/20/2025 12:37
Updated: 06/24/2025 06:45
Changes: 06/20/2025 12:37 (68), 06/24/2025 06:45 (1)
Complete: 🔍
Cache ID: 216::103

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