How this vulnerability can be exploited
This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity high, availability high.
CVSS metrics in full
The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack vector: Network — reachable from anywhere that can route to the service.
- Attack complexity: Low — the attack works reliably, with no preparation.
- Privileges required: None — an unauthenticated stranger can try it.
- User interaction: None — nobody has to be tricked into anything.
- Scope: Unchanged — the damage stays inside the vulnerable component.
- Confidentiality impact: High — total loss, or loss the attacker controls.
- Integrity impact: High — total loss, or loss the attacker controls.
- Availability impact: High — total loss, or loss the attacker controls.
Weakness class
CVE-2026-53421 is classified as CWE-653: Improper Isolation or Compartmentalization. The product does not properly compartmentalize or isolate functionality, processes, or resources that require different privilege levels, rights, or permissions.
Affected software
CVE-2026-53421 is recorded against 1 package.
- syncope (from 4.1.0 up to 4.1.2)
Timeline and source
Published on 20 July 2026 and last revised on 27 July 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.
References
lists.apache.org
www.openwall.com
Other advisories for this package
syncope has other advisories on record. If you are patching this one, these are worth checking on the same host:
Same weakness in other software
These advisories are the same class of weakness (CWE-653: Improper Isolation or Compartmentalization) in other software:
