Vulnerabilities
Misconfiguration
Runtime Security
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CVE Vulnerabilities

CVE-2021-28374

Incorrect Permission Assignment for Critical Resource

Published: Mar 15, 2021 | Modified: Nov 21, 2024
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS 2.x
5 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N
RedHat/V2
RedHat/V3
Ubuntu
MEDIUM
Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-28374
CWEhttps://cwe.mitre.org/data/definitions/732.html

The Debian courier-authlib package before 0.71.1-2 for Courier Authentication Library creates a /run/courier/authdaemon directory with weak permissions, allowing an attacker to read user information. This may include a cleartext password in some configurations. In general, it includes the users existence, uid and gids, home and/or Maildir directory, quota, and some type of password information (such as a hash).

Weakness

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.

Affected Software

Name Vendor Start Version End Version
Courier-authlib Debian * 0.71.1-2 (excluding)
Courier-authlib Ubuntu bionic *
Courier-authlib Ubuntu esm-apps/bionic *
Courier-authlib Ubuntu esm-apps/focal *
Courier-authlib Ubuntu esm-apps/jammy *
Courier-authlib Ubuntu esm-apps/xenial *
Courier-authlib Ubuntu focal *
Courier-authlib Ubuntu groovy *
Courier-authlib Ubuntu hirsute *
Courier-authlib Ubuntu impish *
Courier-authlib Ubuntu jammy *
Courier-authlib Ubuntu kinetic *
Courier-authlib Ubuntu trusty *
Courier-authlib Ubuntu upstream *
Courier-authlib Ubuntu xenial *

Potential Mitigations

  • Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
  • OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
  • This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
  • Be careful to avoid CWE-243 and other weaknesses related to jails.

References

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