Weakness (CWE)
CWE-479: Signal Handler Use of a Non-reentrant Function
The product defines a signal handler that calls a non-reentrant function.
More detail
The function call syslog() is an example of this. In order to perform its functionality, it allocates a small amount of memory as "scratch space." If syslog() is suspended by a signal call and the signal handler calls syslog(), the memory used by both of these functions enters an undefined, and possibly, exploitable state. Implementations of malloc() and free() manage metadata in global structures in order to track which memory is allocated versus which memory is available, but they are non-reentrant. Simultaneous calls to these functions can cause corruption of the metadata.
How to prevent it (4 mitigations)
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Requirements
Require languages or libraries that provide reentrant functionality, or otherwise make it easier to avoid this weakness.
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Architecture and Design
Design signal handlers to only set flags rather than perform complex functionality.
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Implementation
Ensure that non-reentrant functions are not found in signal handlers.
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Implementation
Use sanity checks to reduce the timing window for exploitation of race conditions. This is only a partial solution, since many attacks might fail, but other attacks still might work within the narrower window, even accidentally.
Source: MITRE CWE-479
2 results · Feed
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High 8.6CVE-2026-44011 Public exploit
Craft CMS: Potential authenticated Remote Code Execution via malicious attached Behavior
Craft CMS is a content management system (CMS). From 4.0.0 to before 4.17.12 and 5.9.18, Craft CMS which contains an input-handling flaw in a Yii object creation path that let any authenticated user inject malicious configuration and execute arbitrary command…
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Unscored —
Null pointer dereference in the htmldoc v1.9.11 and before may allow attackers to execute arbitrary code and cause a de…