CVE-2021-43890High· 7.1▾ Abyssal⚠ Exploited in the wild0dayWe have investigated reports of a spoofing vulnerability in AppX installer that affects Microsoft Windows. Microsoft is aware of attacks that attempt to exploit this vulnerability by using specially crafted packages that include the malw…
▾ Abyssal zone — Critical with a public exploit or in-the-wild use
impact 39.1 · likelihood 2.1 · exploitation 25 · ransomware 5
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Exploit-prediction probability, daily snapshots since Aug 4.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Federal remediation due Dec 29, 2021
Last analysed / modified upstream
10%
Added to the CISA catalog on Dec 15, 2021. Federal remediation due Dec 29, 2021. View catalog ↗
We have investigated reports of a spoofing vulnerability in AppX installer that affects Microsoft Windows. Microsoft is aware of attacks that attempt to exploit this vulnerability by using specially crafted packages that include the malware family known as Emotet/Trickbot/Bazaloader. An attacker could craft a malicious attachment to be used in phishing campaigns. The attacker would then have to convince the user to open the specially crafted attachment. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. Please see the Security Updates table for the link to the updated app. Alternatively you can download and install the Installer using the links provided in the FAQ section. Please see the Mitigations and Workaround sections for important information about steps you can take to protect your system from this vulnerability. December 27 2023 Update: In recent months, Microsoft Threat Intelligence has seen an increase in activity from threat actors leveraging social engineering and phishing techniques to target Windows OS users and utilizing the ms-appinstaller URI scheme. To address this increase in activity, we have updated the App Installer to disable the ms-appinstaller protocol by default and recommend other potential mitigations.
app_installer < 1.16app_installer < 1.11Upgrade past the affected range:
app_installer 1.11Connected by shared product, vendor, weakness, or advisory.
CVE-2026-85880High· 7.8Heap-based buffer overflow in Windows ALPC allows an authorized attacker to elevate privileges locally.
CVE-2026-81963High· 7.8Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.
CVE-2026-68821High· 7.3Improper privilege management in Windows Package Manager allows an authorized attacker to elevate privileges locally.
CVE-2026-88097High· 8.1Use after free in Microsoft Edge (Chromium-based) allows an unauthorized attacker to elevate privileges locally.
CVE-2026-62874Critical· 10.0Insufficient verification of data authenticity in Azure Billing allows an unauthorized attacker to elevate privileges over a network.
CVE-2026-85878Critical· 9.9Improper authorization in Azure Database for PostgreSQL allows an authorized attacker to elevate privileges over a network.