Описание
ImageMagick is free and open-source software used for editing and manipulating digital images. The shipped "secure" security policy includes a rule intended to prevent reading/writing from standard streams. However, ImageMagick also supports fd: pseudo-filenames (e.g., fd:0, fd:1). Prior to versions 7.1.2-15 and 6.9.13-40, this path form is not blocked by the secure policy templates, and therefore bypasses the protection goal of "no stdin/stdout." Versions 7.1.2-15 and 6.9.13-40 contain a patch by including a change to the more secure policies by default. As a workaround, add the change to one's security policy manually.
A flaw was found in ImageMagick. The "secure" security policy, intended to prevent reading and writing from standard streams, can be bypassed. An attacker can exploit this by using fd: pseudo-filenames, which are not properly blocked by the policy. This allows the attacker to circumvent the intended security restrictions, potentially leading to unauthorized access to standard input/output (stdin/stdout) and subsequent information disclosure or data manipulation.
Отчет
This MODERATE impact flaw in ImageMagick allows a security policy bypass through the use of fd:<n> pseudo-filenames, enabling unauthorized access to standard input/output despite the "secure" policy. Red Hat Enterprise Linux 6 ELS and 7 ELS, as well as community projects like Fedora and EPEL, are affected by this vulnerability. Exploitation requires an attacker to provide a specially crafted image or command that leverages this bypass.
Меры по смягчению последствий
To mitigate this issue, modify the ImageMagick security policy file, typically located at /etc/ImageMagick-X/policy.xml (where X is the version), to explicitly deny access to fd: pseudo-filenames. Add a policy rule similar to <policy domain="delegate" rights="none" pattern="fd:*" /> within the <policymap> section. This change will prevent ImageMagick from processing fd: paths, thereby closing the bypass. A restart of any services utilizing ImageMagick may be required for the policy change to take effect.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 6 | ImageMagick | Out of support scope | ||
| Red Hat Enterprise Linux 7 | ImageMagick | Out of support scope |
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Дополнительная информация
Статус:
5.9 Medium
CVSS3
Связанные уязвимости
ImageMagick is free and open-source software used for editing and manipulating digital images. The shipped "secure" security policy includes a rule intended to prevent reading/writing from standard streams. However, ImageMagick also supports fd:<n> pseudo-filenames (e.g., fd:0, fd:1). Prior to versions 7.1.2-15 and 6.9.13-40, this path form is not blocked by the secure policy templates, and therefore bypasses the protection goal of "no stdin/stdout." Versions 7.1.2-15 and 6.9.13-40 contain a patch by including a change to the more secure policies by default. As a workaround, add the change to one's security policy manually.
ImageMagick is free and open-source software used for editing and manipulating digital images. The shipped "secure" security policy includes a rule intended to prevent reading/writing from standard streams. However, ImageMagick also supports fd:<n> pseudo-filenames (e.g., fd:0, fd:1). Prior to versions 7.1.2-15 and 6.9.13-40, this path form is not blocked by the secure policy templates, and therefore bypasses the protection goal of "no stdin/stdout." Versions 7.1.2-15 and 6.9.13-40 contain a patch by including a change to the more secure policies by default. As a workaround, add the change to one's security policy manually.
ImageMagick is free and open-source software used for editing and mani ...
ImageMagick's Security Policy Bypass through config/policy-secure.xml via "fd handler" leads to stdin/stdout access
Уязвимость реализации политики безопасности консольного графического редактора ImageMagick, позволяющая нарушителю получить несанкционированный доступ к защищаемой информации
5.9 Medium
CVSS3