--- id: "CVE-2026-105133" kind: "vulnerability" aliases: ["CVE-2026-105133"] title: "ahsay cloud backup suite: A vulnerability was detected in Ahsay AhsayCBS up to 10.3.2" severity: "critical" cvss: 7.5 epss: null exploited: true status: "open" category: "vendor" products: [{"name": "Ahsay AhsayCBS", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "Ahsay AhsayCBS", "fixed": ["10.3.4.45", "9.15.2.70"], "affected": "v7-v9 < 9.15.2.70; v10 <= 10.3.4.0 (< 10.3.4.45)", "ecosystem": "vendor"}, {"name": "ahsay cloud backup suite", "fixed": ["10.3.4"], "affected": "< 10.3.4", "ecosystem": "vendor"}] ecosystems: ["vendor"] tags: ["ahsay", "ahsaycbs", "backup-servers", "exploited", "poc-public", "self-hosted", "vendor", "webshell"] not_affected_if: ["managed-hosting"] published_at: "2026-10-04T07:16:33+00:00" first_seen_at: "2026-10-23T19:11:50+00:00" updated_at: "2026-10-23T23:44:52+00:00" sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-105133", "first_seen_at": "2026-10-23T19:11:50+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-10-23T20:15:20+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-105133", "first_seen_at": "2026-10-23T23:44:52+00:00"}] --- # ahsay cloud backup suite: A vulnerability was detected in Ahsay AhsayCBS up to 10.3.2 AhsayCBS authentication bypass in the JSON API (checkSysPwd is skipped). It is chained with CVE-2026-105134 for unauthenticated RCE. It has been exploited since about Oct 7 to drop JSP webshells and XMRig miners. A public PoC exists. Hotfixes 10.3.4.45 (v10) and 9.15.2.70 (v7-v9) fix it. The earlier 10.3.4.0 and 9.15.2.59 builds do not. _Summary, check and fix written by a model from the sources; labelled as such._ ## Affected - vendor:Ahsay AhsayCBS affected ? fixed ? - vendor:Ahsay AhsayCBS affected v7-v9 < 9.15.2.70; v10 <= 10.3.4.0 (< 10.3.4.45) fixed 10.3.4.45, 9.15.2.70 - vendor:ahsay cloud backup suite affected < 10.3.4 fixed 10.3.4 ## How to check Check the installed AhsayCBS build. Anything below 10.3.4.45 (v10) or 9.15.2.70 (v7/v8/v9) is exposed, including 10.3.4.0 and 9.15.2.59. Then look for signs of compromise (Ahsay's list): odd folders at the drive root (ahsay_ts, ahsay_t8, ahsay_t9, ahsay_t20, ahsay_t21, srv, user, opt); randomly named .jsp files or short random folders in %CBS%\webapps; RPS receivers you did not add; unknown Admin-type AhsayCBS users. Huntress also saw an XMRig miner posing as edge.exe and a fake Edge update Windows service. ## Fix Apply hotfix 10.3.4.45 on v10, or 9.15.2.70 on v9 (v7/v8: upgrade to 9.15.0.0 first, then apply the hotfix), then reboot. Download needs an Ahsay partner login. If any compromise indicator is present, Ahsay advises a full rebuild: reinstall the OS, install 9.15.0.0 or 10.3.4.0 plus the hotfix, and restore an Auto Save config from before the compromise. Until then, restrict the management interface to trusted IPs or a VPN. ## Timeline - 2026-10-23T19:11:50+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-105133 - 2026-10-23T20:15:20+00:00 analyst — Ahsay's advisories (Oct 12/13) give hotfixes 10.3.4.45 and 9.15.2.70; earlier patches 10.3.4.0 and 9.15.2.59 were incomplete. Exploited since Oct 7 (Huntress), public PoC (Horizon3). Same chain as CVE-2026-105134 (OS command injection / upload RCE). Horizon3 describes the bypass as FromServlet=Y skipping checkSysPwd, which differs from the KEV wording about the 'random' parameter. The hotfix download needs a partner login. The v7/v8 fixed version is the v9 hotfix, per Ahsay. - 2026-10-23T23:44:52+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-105133 ## Documents - [advisory] Ahsay: Critical Security Alert update CVE-2026-105133/105134 https://www.ahsay.com/en/company/announcements/patch-cve-105133-105134-update - [describes] Horizon3: CVE-2026-105133 & CVE-2026-105134 AhsayCBS https://horizon3.ai/attack-research/vulnerabilities/cve-2026-105133-and-cve-2026-105134/ - [discussion] Huntress: Threat Actors Exploit Critical AhsayCBS Flaws https://www.huntress.com/blog/ahsaycbs-flaws-exploit - [mentions] Rescana: AhsayCBS CVE-2026-105133/105134 analysis https://www.rescana.com/post/ahsaycbs-cve-2026-105133-105134-exploited-backup-console-rce - [mitigation] Ahsay: AhsayCBS Vulnerability Status Update https://www.ahsay.com/en/company/announcements/ahsaycbs-vulnerability-status-update - [poc] AhsayCBS-Auth-Bypass-RCE PoC (Horizon3, via Kitploit) https://kitploit.com/en/tools/github/horizon3ai/ahsaycbs-auth-bypass-rce ## From the sources Ahsay AhsayCBS contains an improper authentication vulnerability that could allow a remote attacker to bypass authentication via manipulation of the random parameter in the API component’s checkSysPwd function. This vulnerability can be chained with CVE-2026-105134. CISA 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. --- _Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_