CVE-2026-87886

Acronis Backup Incorrect Default Permissions Vulnerability

Exploited in attacks High 7.8 Attack chance: 0.2%

What it is

Local privilege escalation due to insecure file permissions. The following products are affected: Acronis Backup plugin for cPanel & WHM (Linux) before build 1.9.3.1021, Acronis Backup extension for Plesk (Linux) before build 1.8.11.638, Acronis Backup plugin for DirectAdmin (Linux) before build 1.2.3.238.

CISA: Acronis Backup plugin for cPanel & WHM and extension for Plesk contains an incorrect default permissions vulnerability that could allow for privilege escalation.

What to do

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Deadline for US federal agencies: September 19, 2026

security-advisory.acronis.com/advisories/SEC-10986

Added to the CISA list: September 16, 2026
Published: September 17, 2026
Severity: High 7.8 CVSS 3.0
Chance of attacks in the next 30 days (EPSS): 0.2% in the top 85.9% of all known vulnerabilities
Weakness: CWE-276
More details: NVD · CVE.org · CISA

More exploited flaws from Acronis

Added	Vulnerability	Product	Severity	Attack chance
Jul 29, 2024	Insecure Default PasswordCVE-2023-45249	Cyber Infrastructure (ACI)	Critical 9.8	53%

All of them →

Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.