- Reported
- 
        
      
- Issued
- 
        
        
        
        
      
- Package
- 
        
        
        linked_list_allocator
          (crates.io)
        
        
      
- Type
- 
        
        Vulnerability
        
      
- Categories
- 
        
      
- Aliases
- 
        
      
- References
- 
        
      
- CVSS Score
- 8.4 
        HIGH
      
- CVSS Details
- 
        
          
            - Attack Vector
- Local
- Attack Complexity
- Low
- Privileges Required
- None
- User Interaction
- None
- Scope
- Unchanged
- Confidentiality Impact
- High
- Integrity Impact
- High
- Availability Impact
- High
 
- CVSS Vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Patched
- 
        
        
        
      
Description
    
- The heap initialization methods were missing a minimum size check for the given heap size argument. This could lead to out-of-bound writes when a heap was initialized with a size smaller than 3 * size_of::<usize>because of metadata write operations.
- When calling Heap::extendwith a size smaller than twousizes (e.g., 16 onx86_64), the size was erroneously rounded up to the minimum size, which could result in an out-of-bounds write.
- Calling Heap::extendon an empty heap tried to construct a heap starting at address 0, which is also an out-of-bounds write.
- One specific way to trigger this accidentally is to call Heap::new(or a similar constructor) with a heap size that is smaller than twousizes. This was treated as an empty heap as well.
 
- Calling Heap::extendon a heap whose size is not a multiple of the size of twousizes resulted in unaligned writes. It also left the heap in an unexpected state, which might lead to subsequent issues. We did not find a way to exploit this undefined behavior yet (apart from DoS on platforms that fault on unaligned writes).
Advisory available under CC0-1.0
    license.