CVE-2019-0991
Chakra Scripting Engine Memory Corruption Vulnerability
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge (HTML-based). The vulnerability could corrupt memory in such a way that an attacker could 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, an attacker who successfully exploited the vulnerability 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. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge (HTML-based) and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
4.2
Chakra Scripting Engine Memory Corruption Vulnerability
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge (HTML-based). The vulnerability could corrupt memory in such a way that an attacker could 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, an attacker who successfully exploited the vulnerability 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. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge (HTML-based) and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.
- Record
CVE-2019-0991- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N/E:P/RL:O/RC:C - Updated
- 2026-11-02
EUVDEUVD-2021-0617
4.2
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge (HTML-based). The vulnerability could corrupt memory in such a way that an attacker could 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, an attacker who successfully exploited the vulnerability 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. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge (HTML-based) and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.
- Record
EUVD-2021-0617- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N/E:P/RL:O/RC:C - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6973-94v8-5mgw
7.5
Chakra Scripting Engine Out-of-bounds write
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge (HTML-based). The vulnerability could corrupt memory in such a way that an attacker could 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, an attacker who successfully exploited the vulnerability 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. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge (HTML-based) and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.
- Record
GHSA-6973-94v8-5mgw- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
NVD
4.2
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge (HTML-based). The vulnerability could corrupt memory in such a way that an attacker could 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, an attacker who successfully exploited the vulnerability 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. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge (HTML-based) and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.
- Record
CVE-2019-0991- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N - CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.6 High
AV:N/AC:H/Au:N/C:C/I:C/A:C - Weakness
- CWE-787
- Updated
- 2026-11-02
OSV
4.2
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge (HTML-based). The vulnerability could corrupt memory in such a way that an attacker could 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, an attacker who successfully exploited the vulnerability 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. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge (HTML-based) and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.
- Record
CVE-2019-0991- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
OSVGHSA-6973-94v8-5mgw
7.5
Chakra Scripting Engine Out-of-bounds write
A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge (HTML-based). The vulnerability could corrupt memory in such a way that an attacker could 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, an attacker who successfully exploited the vulnerability 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. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge (HTML-based) and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.
- Record
GHSA-6973-94v8-5mgw- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
Microsoft.ChakraCoreNuGet |
before 1.11.10 | 1.11.10 |
Microsoft.ChakraCoreNuGet |
before 1.11.10, plus listed versions 1.10.01.10.11.10.21.11.01.11.1 Show 41 moreShow less1.11.21.11.31.11.41.11.51.11.61.11.71.11.81.11.91.2.01.2.11.2.21.2.31.2.6.62716-preview1.3.01.3.11.3.21.4.01.4.11.4.21.4.31.4.41.4.51.5.01.5.11.5.21.5.31.6.01.6.21.7.01.7.11.7.21.7.31.7.41.7.51.7.61.8.01.8.11.8.21.8.31.8.41.8.5 |
1.11.10 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-0991 is a medium vulnerability (CVSS 4.2) in Microsoft Edge, published June 12, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.47%, the 84th percentile. Fixed in Microsoft.ChakraCore 1.11.10.
References
msrc.microsoft.com/update-guide/vulnerability/CVE-2019-0991
portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0991
nvd.nist.gov/vuln/detail/CVE-2019-0991
github.com/chakra-core/ChakraCore/commit/1caa4118796d33513bc40ce894c053a92de98abb
github.com/chakra-core/ChakraCore/commit/3d6226cc2d1077537220361c82e34a362c6c76ee
github.com/advisories/GHSA-6973-94v8-5mgw
github.com/chakra-core/ChakraCore