CVE-2026-62886 in .NET
Summary
by MITRE • 08/11/2026
Integer overflow or wraparound in .NET allows an unauthorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 08/11/2026
This vulnerability represents a critical security flaw in the .NET runtime environment that enables local privilege escalation through integer overflow conditions. The issue occurs when arithmetic operations involving integer variables exceed their maximum representable values, causing the values to wrap around to negative numbers or zero, which can then be exploited by malicious actors to manipulate memory access patterns and bypass security controls. Such vulnerabilities fall under the common weakness enumeration CWE-190, specifically addressing integer overflow conditions that can lead to unpredictable behavior in software applications.
The technical implementation of this flaw typically involves scenarios where .NET applications perform calculations with user-supplied data without proper bounds checking or validation mechanisms. When an attacker can influence input parameters that are subsequently used in arithmetic operations within the runtime environment, they may be able to cause integer wraparound conditions that result in memory corruption or access violations. The vulnerability is particularly dangerous in local contexts because it allows attackers who already have limited system access to potentially escalate their privileges to higher security levels such as administrator or root access. This type of attack aligns with ATT&CK technique T1068 which describes the exploitation of vulnerabilities to elevate privileges.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it can enable attackers to manipulate application behavior in ways that compromise system integrity and confidentiality. When integer overflows occur within .NET framework components or applications built on this platform, they can create opportunities for memory corruption attacks that may lead to code execution or information disclosure. The local nature of the attack means that exploitation typically requires an initial foothold on the target system, but once achieved, the attacker can leverage the vulnerability to gain elevated privileges without requiring additional authentication mechanisms.
Mitigation strategies should focus on implementing comprehensive input validation and bounds checking within .NET applications, particularly in scenarios involving arithmetic operations with user-supplied data. Developers must ensure that all integer calculations include proper overflow detection mechanisms and that applications perform adequate validation before processing potentially malicious inputs. Organizations should also implement regular security updates and patches for .NET runtime environments, as Microsoft typically addresses such vulnerabilities through their regular security release cycles. Additionally, deployment of runtime monitoring tools and application whitelisting can help detect anomalous behavior patterns that may indicate exploitation attempts. The use of address space layout randomization and other exploit mitigation techniques can also reduce the effectiveness of potential attacks leveraging integer overflow conditions.