CVEs / CVE-2026-87886
CVE-2026-87886: Acronis Backup Incorrect Default Permissions Vulnerability
- Known exploited in the CISA KEV catalog since 16 Sep 2026
- high 7.8 CVSS 3.0 (from the CNA)
- EPSS 0.23% chance of exploitation in the next 30 days, higher than 14% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Acronis Backup plugin for cPanel & WHM and extension for Plesk contains an incorrect default permissions vulnerability that could allow for privilege escalation.
Description
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Acronis Acronis Backup plugin for cPanel & WHM | from unspecified, before 1.9.3.1021 | 1.9.3.1021 |
| Acronis Acronis Backup extension for Plesk | from unspecified, before 1.8.11.638 | 1.8.11.638 |
| Acronis Acronis Backup plugin for DirectAdmin | from unspecified, before 1.2.3.238 | 1.2.3.238 |
Exploitation
| In CISA KEV since | 16 Sep 2026 |
|---|---|
| Due date for US federal agencies | 19 Sep 2026 |
| Used in ransomware campaigns | Unknown |
| Required action | 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. |
Severity
| CVSS 3.0 | 7.8 highCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-276 |
References
- CVE-2026-87886 on NVD
- CVE-2026-87886 in the CISA KEV catalog
- https://security-advisory.acronis.com/advisories/SEC-10986 (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk (cited by CISA)
- https://security-advisory.acronis.com/advisories/SEC-10986 Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-87886 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.