Weakness · Medium
CWE-65: Windows Hard Link
What it is
The product, when opening a file or directory, does not sufficiently handle when the name is associated with a hard link to a target that is outside of the intended control sphere. This could allow an attacker to cause the product to operate on unauthorized files.
- Severity (our rating)
- Medium
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Implementation, Operation
- Exploited in the wild
- No CVE in CISA's catalog
In more detail
Failure for a system to check for hard links can result in vulnerability to different types of attacks. For example, an attacker can escalate their privileges if a file used by a privileged program is replaced with a hard link to a sensitive file (e.g. AUTOEXEC.BAT). When the process opens the file, the attacker can assume the privileges of that process, or prevent the program from accurately processing data.
What an attacker can do
- Read Files or Directories (Confidentiality, Integrity)
- Modify Files or Directories (Confidentiality, Integrity)
How to prevent it
Architecture and Design
- Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.