CVE-2016-3247
published 2016-09-14CVE-2016-3247: Microsoft Internet Explorer 11 and Microsoft Edge allow remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a…
PriorityP267high7.5CVSS 3.0
AVNACHPRNUIRSUCHIHAH
EXPLOIT
EPSS
71.48%
99.3th percentile
Microsoft Internet Explorer 11 and Microsoft Edge allow remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted web site, aka "Microsoft Browser Memory Corruption Vulnerability."
Affected
17 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | internet_explorer | — | — |
| msrc | internet_explorer_11_on_windows_10_for_32-bit_systems | — | — |
| msrc | internet_explorer_11_on_windows_10_for_x64-based_systems | — | — |
| msrc | internet_explorer_11_on_windows_10_version_1511_for_32-bit_systems | — | — |
| msrc | internet_explorer_11_on_windows_10_version_1511_for_x64-based_systems | — | — |
| msrc | internet_explorer_11_on_windows_10_version_1607_for_32-bit_systems | — | — |
| msrc | internet_explorer_11_on_windows_10_version_1607_for_x64-based_systems | — | — |
| msrc | internet_explorer_11_on_windows_8.1_for_32-bit_systems | — | — |
| msrc | internet_explorer_11_on_windows_8.1_for_x64-based_systems | — | — |
| msrc | internet_explorer_11_on_windows_rt_8.1 | — | — |
| msrc | internet_explorer_11_on_windows_server_2012_r2 | — | — |
| msrc | microsoft_edge_on_windows_10_for_32-bit_systems | — | — |
| msrc | microsoft_edge_on_windows_10_for_x64-based_systems | — | — |
| msrc | microsoft_edge_on_windows_10_version_1511_for_32-bit_systems | — | — |
| msrc | microsoft_edge_on_windows_10_version_1511_for_x64-based_systems | — | — |
| msrc | microsoft_edge_on_windows_10_version_1607_for_32-bit_systems | — | — |
| msrc | microsoft_edge_on_windows_10_version_1607_for_x64-based_systems | — | — |
Detection & IOCsextracted from sources · hover to see the quote
- →Trigger is a crafted HTML page combining CSS rules `*::first-letter{ border: 0; }` and `*{ white-space: pre-line; }` — detect pages serving both selectors together as a suspicious pattern targeting CTextExtractor::GetBlockText in Microsoft Edge/IE11. ↗
- →The vulnerability is an integer underflow in a 32-bit index variable inside CTextExtractor::GetBlockText, causing an out-of-bounds read of ~8 GB (0x200000000 bytes) beyond the buffer on 64-bit Edge. Monitor for Edge/IE11 processes consuming abnormally large memory (5–10 GB) consistent with a heap spray attempting to populate the OOB address range. ↗
- →PoC heap spray uses a specific allocation-size sequence ([-0x4000, 0x1000, -0x5000, 0x5000, -0x7000, 0x6000, -0x8000]) consuming ~5.3 GB RAM to reach the OOB address; a page causing Edge to allocate 5–10 GB of heap memory via JavaScript ArrayBuffers or typed arrays is a strong indicator of exploitation. ↗
- →Unlike a typical crash-inducing repro, a successful exploit attempt will NOT crash Edge because the heap spray pre-allocates the OOB region; absence of an access-violation crash in Edge while the page is loaded and memory usage is extremely high should be treated as a suspicious indicator rather than a clean signal. ↗
- ·Exploitation only manifests as an ~8 GB OOB read on 64-bit Edge/IE11; on 32-bit systems the integer wrap causes a read only one WCHAR before the buffer start and does not crash, making 32-bit systems harder to detect via crash telemetry. ↗
- ·Internet Explorer running in Enhanced Security Configuration (ESC) on Windows Server 2008/2008 R2/2012/2012 R2 reduces exploitation likelihood; ESC is a mitigating factor only for sites not in the Trusted Sites zone. ↗
- ·EMET can help mitigate exploitation of this memory-corruption vulnerability in Internet Explorer when installed and configured to work with IE. ↗
CVSS provenance
nvdv3.07.5HIGHCVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.05.1MEDIUMAV:N/AC:H/Au:N/C:P/I:P/A:P
vendor_msrc4.2MEDIUM
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Microsoft
Microsoft Browser Memory Corruption Vulnerability
vendor_msrc·2016-09-13·CVSS 4.2
CVE-2016-3247 [HIGH] Microsoft Browser Memory Corruption Vulnerability
Microsoft Browser Memory Corruption Vulnerability
Description: A remote code execution vulnerability exists in the way that Microsoft browsers access objects in memory. The vulnerability could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, the attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
An attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft browsers, and then convince
GHSA
GHSA-9cvr-8gvg-2wq6: Microsoft Internet Explorer 11 and Microsoft Edge allow remote attackers to execute arbitrary code or cause a denial of service (memory corruption) vi
ghsa_unreviewed·2022-05-14
CVE-2016-3247 [HIGH] GHSA-9cvr-8gvg-2wq6: Microsoft Internet Explorer 11 and Microsoft Edge allow remote attackers to execute arbitrary code or cause a denial of service (memory corruption) vi
Microsoft Internet Explorer 11 and Microsoft Edge allow remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted web site, aka "Microsoft Browser Memory Corruption Vulnerability."
No detection rules found.
http://blog.skylined.nl/20161118002.htmlhttp://seclists.org/fulldisclosure/2016/Nov/111http://www.securityfocus.com/archive/1/539779/100/0/threadedhttp://www.securityfocus.com/bid/92828http://www.securitytracker.com/id/1036788http://www.securitytracker.com/id/1036789https://docs.microsoft.com/en-us/security-updates/securitybulletins/2016/ms16-104https://docs.microsoft.com/en-us/security-updates/securitybulletins/2016/ms16-105https://www.exploit-db.com/exploits/40797/http://blog.skylined.nl/20161118002.htmlhttp://seclists.org/fulldisclosure/2016/Nov/111http://www.securityfocus.com/archive/1/539779/100/0/threadedhttp://www.securityfocus.com/bid/92828http://www.securitytracker.com/id/1036788http://www.securitytracker.com/id/1036789https://docs.microsoft.com/en-us/security-updates/securitybulletins/2016/ms16-104https://docs.microsoft.com/en-us/security-updates/securitybulletins/2016/ms16-105https://www.exploit-db.com/exploits/40797/
2016-09-14
Published