CVE-2021-23984

Una extensión maliciosa podría haber abierto una ventana emergente sin una barra de direcciones. El título de la ventana emergente que carece de una barra de direcciones no debería ser totalmente controlable, pero en esta situación sí lo era. Esto podría haber sido usado para falsificar un sitio web e intentar engañar al usuario para que proporcione credenciales. Esta vulnerabilidad afecta a Firefox ESR versiones anteriores a 78.9, Firefox versiones anteriores a 87, and Thunderbird versiones anteriores a 78.9

The Mozilla Foundation Security Advisory describes this issue as: A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address bar should not be fully controllable, but in this situation was. This could have been used to spoof a website and attempt to trick the user into providing credentials.

USN-4995-1 fixed vulnerabilities in Thunderbird. This update provides the corresponding updates for Ubuntu 18.04 LTS. Multiple security issues were discovered in Thunderbird. If a user were tricked into opening a specially crafted website in a browsing context, an attacker could potentially exploit these to cause a denial of service, obtain sensitive information, spoof the UI, bypass security restrictions, or execute arbitrary code. It was discovered that extensions could open popup windows with control of the window title in some circumstances. If a user were tricked into installing a specially crafted extension, an attacker could potentially exploit this to spoof a website and trick the user into providing credentials. Multiple security issues were discovered in Thunderbird's OpenPGP integration. If a user were tricked into importing a specially crafted key in some circumstances, an attacker could potentially exploit this to cause a denial of service or confuse the user. A use-after-free was discovered when Responsive Design Mode was enabled. If a user were tricked into opening a specially crafted website with Responsive Design Mode enabled, an attacker could potentially exploit this to cause a denial of service, or execute arbitrary code. It was discovered that Thunderbird mishandled ftp URLs with encoded newline characters. If a user were tricked into clicking on a specially crafted link, an attacker could potentially exploit this to send arbitrary FTP commands. It was discovered that Thunderbird wrote signatures to disk and read them back during verification. A local attacker could potentially exploit this to replace the data with another signature file. It was discovered that Thunderbird might load an alternative OTR library. If a user were tricked into copying a specially crafted library to one of Thunderbird's search paths, an attacker could potentially exploit this to execute arbitrary code. It was discovered that secret keys imported into Thunderbird were stored unencrypted. A local attacker could potentially exploit this to obtain private keys. It was discovered that Thunderbird did not indicate when an inline signed or encrypted message contained additional unprotected parts. Various other issues were also addressed.