CVE-2026-39855
Description
A flaw was found in osslsigncode. An integer underflow vulnerability exists in the PE page-hash computation code. A remote attacker could craft a malicious Portable Executable (PE) file where the SizeOfHeaders is larger than SectionAlignment. When this file is processed, either during signing with page hashing enabled or during verification of an already signed file, the integer underflow leads to an out-of-bounds read, causing the process to crash, and resulting in a denial of service.
Statement
Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Instability
This weakness will generally lead to undefined behavior and therefore crashes. In the case of overflows involving loop index variables, the likelihood of infinite loops is also high.
Integrity
Technical Impact: Modify Memory
If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.
Confidentiality,Availability,Access Control
Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism
This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.
Frequently Asked Questions
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