CVE-2025-5963

TCC Bypass via Dylib Injection in Postbox

MEDIUM
4.8
CVSS Score
Published: June 20, 2025 at 10:01 AM UTC
Updated: June 17, 2026 at 09:49 AM UTC
1 product affected across 1 vendorPostbox

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Severity
MEDIUM4.8
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.8MEDIUMCERT-PL
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-276

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