CVE-2025-24903: Whisperfish Libsignal-Service-RS

High severity, CVSS 8.5. EPSS: 0.2% chance of exploitation in the next 30 days.

libsignal-service-rs is a Rust version of the libsignal-service-java library which implements the core functionality to communicate with Signal servers. Prior to commit 82d70f6720e762898f34ae76b0894b0297d9b2f8, any contact may forge a sync message, impersonating another device of the local user. The origin of sync messages is not checked. Patched libsignal-service can be found after commit 82d70f6720e762898f34ae76b0894b0297d9b2f8. The `Metadata` struct contains an additional `was_encrypted` field, which breaks the API, but should be easily resolvable. No known workarounds are available.

Affected products

• Whisperfish Libsignal-Service-RS: before 82d70f6720e762898f34ae76b0894b0297d9b2f8 (fixed in 82d70f6720e762898f34ae76b0894b0297d9b2f8)

Published 2025-02-13. Last modified 2026-06-17.