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CVE Vulnerabilities

CVE-2020-15656

Access of Resource Using Incompatible Type ('Type Confusion')

Published: Aug 10, 2020 | Modified: Nov 21, 2024
CVSS 3.x
8.8
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.x
9.3 HIGH
AV:N/AC:M/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
8.8 MODERATE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2020-15656
CWEhttps://cwe.mitre.org/data/definitions/843.html

JIT optimizations involving the Javascript arguments object could confuse later optimizations. This risk was already mitigated by various precautions in the code, resulting in this bug rated at only moderate severity. This vulnerability affects Firefox ESR < 78.1, Firefox < 79, and Thunderbird < 78.1.

Weakness

The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

Affected Software

NameVendorStart VersionEnd Version
FirefoxMozilla*79.0 (excluding)
Firefox_esrMozilla*78.1 (excluding)
ThunderbirdMozilla*78.1 (excluding)
Red Hat Enterprise Linux 7RedHatfirefox-0:78.3.0-1.el7_9*
Red Hat Enterprise Linux 8RedHatfirefox-0:78.2.0-2.el8_2*
Red Hat Enterprise Linux 8.0 Update Services for SAP SolutionsRedHatfirefox-0:78.2.0-3.el8_0*
Red Hat Enterprise Linux 8.1 Extended Update SupportRedHatfirefox-0:78.2.0-3.el8_1*
FirefoxUbuntubionic*
FirefoxUbuntudevel*
FirefoxUbuntufocal*
FirefoxUbuntugroovy*
FirefoxUbuntuhirsute*
FirefoxUbuntuimpish*
FirefoxUbuntujammy*
FirefoxUbuntukinetic*
FirefoxUbuntulunar*
FirefoxUbuntumantic*
FirefoxUbuntunoble*
FirefoxUbuntutrusty*
FirefoxUbuntuupstream*
FirefoxUbuntuxenial*
Mozjs38Ubuntubionic*
Mozjs38Ubuntuesm-apps/bionic*
Mozjs38Ubuntuupstream*
Mozjs52Ubuntubionic*
Mozjs52Ubuntuesm-apps/focal*
Mozjs52Ubuntuesm-infra/bionic*
Mozjs52Ubuntufocal*
Mozjs52Ubuntugroovy*
Mozjs52Ubuntuupstream*
Mozjs60Ubuntuupstream*
Mozjs68Ubuntuesm-infra/focal*
Mozjs68Ubuntufocal*
Mozjs68Ubuntugroovy*
Mozjs68Ubuntuupstream*
ThunderbirdUbuntubionic*
ThunderbirdUbuntufocal*
ThunderbirdUbuntutrusty*
ThunderbirdUbuntuupstream*
ThunderbirdUbuntuxenial*

Extended Description

When the product accesses the resource using an incompatible type, this could trigger logical errors because the resource does not have expected properties. In languages without memory safety, such as C and C++, type confusion can lead to out-of-bounds memory access. While this weakness is frequently associated with unions when parsing data with many different embedded object types in C, it can be present in any application that can interpret the same variable or memory location in multiple ways. This weakness is not unique to C and C++. For example, errors in PHP applications can be triggered by providing array parameters when scalars are expected, or vice versa. Languages such as Perl, which perform automatic conversion of a variable of one type when it is accessed as if it were another type, can also contain these issues.

References

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