cbcvebase.
CVE-2017-0290
published 2017-05-09

CVE-2017-0290: The Microsoft Malware Protection Engine running on Microsoft Forefront and Microsoft Defender on Microsoft Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1…

PriorityP270high7.8CVSS 3.0
AVLACLPRNUIRSUCHIHAH
EXPLOIT
EPSS
77.21%
99.5th percentile
The Microsoft Malware Protection Engine running on Microsoft Forefront and Microsoft Defender on Microsoft Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, 1607, and 1703, and Windows Server 2016 does not properly scan a specially crafted file leading to memory corruption, aka "Microsoft Malware Protection Engine Remote Code Execution Vulnerability."

Affected

20 ranges
VendorProductVersion rangeFixed in
microsoftmalware_protection_engine<= 1.1.13701.0
microsoft_corporationmicrosoft_malware_protection_engine
msrcmicrosoft_forefront_endpoint_protection_2010
msrcmicrosoft_forefront_security_for_sharepoint_service_pack_3
msrcmicrosoft_security_essentials
msrcwindows_defender_on_windows_10_for_32-bit_systems
msrcwindows_defender_on_windows_10_for_x64-based_systems
msrcwindows_defender_on_windows_10_version_1511_for_32-bit_systems
msrcwindows_defender_on_windows_10_version_1511_for_x64-based_systems
msrcwindows_defender_on_windows_10_version_1607_for_32-bit_systems
msrcwindows_defender_on_windows_10_version_1607_for_x64-based_systems
msrcwindows_defender_on_windows_10_version_1703_for_32-bit_systems
msrcwindows_defender_on_windows_10_version_1703_for_x64-based_systems
msrcwindows_defender_on_windows_7_for_32-bit_systems_service_pack_1
msrcwindows_defender_on_windows_7_for_x64-based_systems_service_pack_1
msrcwindows_defender_on_windows_8.1_for_32-bit_systems
msrcwindows_defender_on_windows_8.1_for_x64-based_systems
msrcwindows_defender_on_windows_rt_8.1
msrcwindows_defender_on_windows_server_2016
msrcwindows_intune_endpoint_protection

Detection & IOCsextracted from sources · hover to see the quote

pathc:\ProgramData\Microsoft\Microsoft Antimalware\Definition Updates\{1C2B7358-645B-41D0-9E79-5FA3E5C4EB51}\mpengine.dll
urlhttps://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/41975.zip
version1.1.13701.0
version1.1.13704.0
  • The vulnerability is triggered by any file written to disk (downloads, email attachments, browser cache, temp files) — MIME type and file extension are irrelevant; MsMpEng uses its own content identification system, so network-level filtering by file type is ineffective.
  • Exploit delivery vectors include email (no user interaction required — reading or opening is not necessary), web browsing, instant messaging, and any mechanism that writes attacker-controlled content to disk.
  • MsMpEng runs as NT AUTHORITY\SYSTEM (S-1-5-18) without sandboxing; successful exploitation results in SYSTEM-level code execution — alert on unexpected child processes or network connections spawned from MsMpEng.exe.
  • The exploit abuses NScript (mpengine's unsandboxed JavaScript interpreter) via a type confusion in JsDelegateObject_Error::toString() — the 'message' property of an Error object is not type-validated before being passed to JsRuntimeState::triggerShortStrEvent(), allowing an integer handle to be treated as a vtable pointer.
  • Deeply nested or obscure archive formats (e.g., Amiga ZOO, MagicISO UIF) can be used to deliver the payload — mpengine unpacks arbitrarily deeply nested archives, making network-level identification impractical.
  • Verify mpengine.dll version on all endpoints; any version at or below 1.1.13701.0 is vulnerable. Detection query: check engine version reported by antimalware software against the patched threshold of 1.1.13704.0.
  • ·On Windows 10, adding a blanket exception for C:\ prevents automatic filesystem scanning by MsMpEng, which would block exploitation — however this also disables real-time protection entirely and is not a recommended mitigation.
  • ·MsMpEng uses a filesystem minifilter to intercept ALL system filesystem activity — any write to disk (including browser caches, temp files, unconfirmed downloads) is sufficient to trigger scanning and thus exploitation, regardless of where the file lands.
  • ·Server-side exposure is significant: Exchange and IIS deployments running affected engine versions are remotely exploitable without authentication, as MsMpEng scans inbound content on those services.

CVSS provenance

nvdv3.07.8HIGHCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
vendor_msrc7.8CRITICAL
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