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CVE Vulnerabilities

CVE-2021-43542

Generation of Error Message Containing Sensitive Information

Published: Dec 08, 2021 | Modified: Nov 21, 2024
CVSS 3.x
6.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N
RedHat/V2
RedHat/V3
6.1 MODERATE
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-43542
CWEhttps://cwe.mitre.org/data/definitions/209.html

Using XMLHttpRequest, an attacker could have identified installed applications by probing error messages for loading external protocols. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Weakness

The product generates an error message that includes sensitive information about its environment, users, or associated data.

Affected Software

NameVendorStart VersionEnd Version
FirefoxMozilla*95.0 (excluding)
Firefox_esrMozilla*91.4.0 (excluding)
ThunderbirdMozilla*91.4.0 (excluding)
Red Hat Enterprise Linux 7RedHatfirefox-0:91.4.0-1.el7_9*
Red Hat Enterprise Linux 7RedHatthunderbird-0:91.4.0-3.el7_9*
Red Hat Enterprise Linux 8RedHatfirefox-0:91.4.0-1.el8_5*
Red Hat Enterprise Linux 8RedHatthunderbird-0:91.4.0-2.el8_5*
Red Hat Enterprise Linux 8.1 Update Services for SAP SolutionsRedHatfirefox-0:91.4.0-1.el8_1*
Red Hat Enterprise Linux 8.1 Update Services for SAP SolutionsRedHatthunderbird-0:91.4.0-2.el8_1*
Red Hat Enterprise Linux 8.2 Extended Update SupportRedHatfirefox-0:91.4.0-1.el8_2*
Red Hat Enterprise Linux 8.2 Extended Update SupportRedHatthunderbird-0:91.4.0-2.el8_2*
Red Hat Enterprise Linux 8.4 Extended Update SupportRedHatfirefox-0:91.4.0-1.el8_4*
Red Hat Enterprise Linux 8.4 Extended Update SupportRedHatthunderbird-0:91.4.0-2.el8_4*
FirefoxUbuntubionic*
FirefoxUbuntudevel*
FirefoxUbuntufocal*
FirefoxUbuntuhirsute*
FirefoxUbuntuimpish*
FirefoxUbuntujammy*
FirefoxUbuntukinetic*
FirefoxUbuntulunar*
FirefoxUbuntumantic*
FirefoxUbuntunoble*
FirefoxUbuntutrusty*
FirefoxUbuntuupstream*
FirefoxUbuntuxenial*
Firefox-esrUbuntutrusty*
Firefox-esrUbuntuupstream*
Firefox-esrUbuntuxenial*
Mozjs38Ubuntubionic*
Mozjs38Ubuntuesm-apps/bionic*
Mozjs38Ubuntuupstream*
Mozjs52Ubuntubionic*
Mozjs52Ubuntuesm-apps/focal*
Mozjs52Ubuntuesm-infra/bionic*
Mozjs52Ubuntufocal*
Mozjs52Ubuntuupstream*
Mozjs68Ubuntuesm-infra/focal*
Mozjs68Ubuntufocal*
Mozjs68Ubuntuupstream*
Mozjs78Ubuntuesm-apps/jammy*
Mozjs78Ubuntuhirsute*
Mozjs78Ubuntuimpish*
Mozjs78Ubuntujammy*
Mozjs78Ubuntukinetic*
Mozjs78Ubuntulunar*
Mozjs78Ubuntuupstream*
ThunderbirdUbuntubionic*
ThunderbirdUbuntudevel*
ThunderbirdUbuntufocal*
ThunderbirdUbuntuhirsute*
ThunderbirdUbuntuimpish*
ThunderbirdUbuntujammy*
ThunderbirdUbuntukinetic*
ThunderbirdUbuntulunar*
ThunderbirdUbuntumantic*
ThunderbirdUbuntunoble*
ThunderbirdUbuntutrusty*
ThunderbirdUbuntuupstream*
ThunderbirdUbuntuxenial*

Potential Mitigations

  • Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success.
  • If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files.
  • Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.

References

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