CVE-2026-47122: Sparkle's AppInstaller post-stage-1 XPC listener accepts unvalidated connections, allowing spoofed appcast item data injection

Description

Sparkle is a software update framework for macOS. In versions up to and including 2.9.1, `Autoupdate/AppInstaller.m`'s `shouldAcceptNewConnection:` only enforces `SUCodeSigningVerifier validateConnection:` before stage 1 completes. After `_performedStage1Installation = YES`, new connections to the registered Mach service `<bundleId>-spki` are accepted from any local process without team-ID or code-signing checks. As of time of publication, no known patched versions are available.

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:L

Attack vector

Local

Complexity

High

Privileges

Low

User interaction

None

Confidentiality

None

Integrity

Low

Availability

Low

Scope

Changed

Exploitation

Is it being used?

Exploit prediction (EPSS)0.1% · higher than 1% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

SP

Sparkle · sparkle-project

<= 2.9.1 · source: vendor, NVD