ROS-2-456

2.456 Multiple vulnerabilities in Mozilla Thunderbird Mozilla Firefox (CVE-2021-23953-CVE-2021-23965, CVE-2021-23991-CVE-2021-23993)

1. Vulnerability Description:

The vulnerability allows a remote attacker to gain access to potentially sensitive information. Vulnerability allows a remote attacker to conduct a spoofing attack. The vulnerability exists due to information leakage from various sources when processing PDF files. A remote attacker could create a specially crafted PDF file, trick the victim into opening it, and gain access to sensitive information via redirected PDF requests when the specified information is delivered as fragmented data. The vulnerability exists due to improper handling of user-supplied data when verifying whether the user ID associated with the OpenPGP key has a valid self-signature. An attacker could create a crafted version of the OpenPGP key by either replacing the original user ID or adding a different user ID. If Thunderbird imports and accepts the created key, the Thunderbird user may mistakenly conclude that the false user ID belongs to the correspondent.Identifier of the Information Security Threat Data Bank of the FSTEC of Russia: BDU:2021-02090, BDU:2021-02089, BDU:2021-02089, BDU:2021-02088, BDU:2021-02087, BDU:2021-02086, BDU:2021-02085, BDU:2021-02084, BDU:2021-02083, BDU:2021-02082, BDU:2021-02081, BDU:2021-02080, BDU:2021-02079, BDU:2021-02078, BDU:2021-02077, BDU:2021-02076

2. Possible remedial actions to address the vulnerability

The user should refrain from opening files from untrusted third parties (paying special attention to PDF files and files signed with OpenPGP key) until the patch is applied or stop using firefox browser and thunderbird email application completely. Or - install security updates for packages: firefox thunderbird**Installing updates is possible in the following ways:**a) if the computer with the installed OS version has access to the vendor’s official repository, you should run the update as administrator with the command:# yum updateAfter the list of updated packages is displayed, agree to apply the updates by pressing the Y key on the keyboard. Wait until the update installation is complete and make sure that there are no errors during its installation.b)If the computer with the installed OS version does not have access to the vendor’s official repository, you should perform the following actions: - download the updated package (with dependencies if necessary): http://repo.red-soft.ru/redos/7.2c/x86_64/updates/thunderbird-78.9.1-0.1.el7.x86_64.rpm http://repo.red-soft.ru/redos/7.2c/x86_64/updates/firefox-78.9.0-0.1.el7.x86_64.rpm Check the package integrity and authenticity by instructionsInstall the downloaded package(s) with the command:# yum localinstall *.rpmWhen the list of updated packages is displayed, agree to apply the updates by pressingY on the keyboard. Wait for the updates to finish installing and make sure there are no errors during the installation.

Date of last modification: 08.09.2021