CVE-2026-79197
Summary
by MITRE • 08/26/2026
Use after free in V8 in Google Chrome prior to 152.0.7977.65 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: Low)
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Analysis
by VulDB Data Team • 08/26/2026
The vulnerability identified as a use-after-free flaw within the V8 JavaScript engine, which powers Google Chrome prior to version 152.0.7977.65, represents a critical memory safety issue that can be leveraged by remote attackers to achieve arbitrary code execution. This specific class of defect occurs when a program continues to use a pointer after the memory it points to has been freed or reallocated. In the context of V8, this typically involves JavaScript objects being garbage collected while still referenced by native C++ components or other active contexts within the engine's runtime environment. When an attacker crafts a malicious HTML page containing specific JavaScript sequences designed to trigger premature deallocation followed by subsequent access, they can manipulate the memory state in ways that bypass standard safety checks. The severity of this vulnerability is classified as low by Chromium security standards, likely due to existing mitigations such as sandboxing or heap hardening techniques that make exploitation difficult, though it remains a significant risk for targeted attacks where exploit reliability is paramount.
From a technical perspective, the core flaw lies in the lifecycle management of objects within the V8 engine's garbage collection system. JavaScript relies on automatic memory management, but when bindings to native code exist or when complex object graphs are manipulated, timing issues can arise between the garbage collector and active execution threads. If an object is freed while a reference to it remains valid in another part of the application logic, accessing that dangling pointer leads to undefined behavior. An attacker exploiting this condition can often control what data resides at the memory address previously occupied by the freed object through techniques such as heap spraying or precise allocation patterns. By carefully controlling the contents of the newly allocated memory block that reuses the same physical location, an attacker can craft a scenario where subsequent reads or writes from the stale reference result in controlled memory corruption. This corruption can be used to overwrite function pointers, return addresses, or other critical control flow data structures within the browser process.
The operational impact of this vulnerability is severe despite its low severity rating because it facilitates remote code execution inside the Chrome sandbox. While modern browsers employ robust sandboxing architectures that restrict what a compromised renderer process can do on the host system, achieving arbitrary code execution remains a primary objective for attackers seeking to escalate privileges or install persistent malware. The ability to execute code within the browser's context allows an attacker to potentially bypass certain security boundaries, access sensitive local resources if permissions are granted, or serve as a foothold for further lateral movement in enterprise environments where Chrome is widely deployed. Users visiting a malicious website containing the crafted HTML page would trigger this vulnerability automatically upon script execution, requiring no additional user interaction beyond loading the page. This makes it particularly dangerous in scenarios involving drive-by downloads or targeted phishing campaigns that rely on social engineering to direct victims to exploit-laden sites.
Mitigation strategies primarily involve updating Google Chrome to version 152.0.7977.65 or later, where these memory management issues have been addressed through code fixes and improved validation checks within the V8 engine. Security teams should ensure that automatic updates are enabled for all endpoints to minimize exposure windows. Additionally, organizations can employ application control policies to restrict the execution of untrusted scripts in high-risk environments or utilize browser hardening configurations that disable JavaScript features most commonly abused by such exploits, although this may impact usability. From a defensive monitoring perspective, detecting attempts to exploit use-after-free vulnerabilities often requires deep packet inspection or endpoint detection and response solutions capable of analyzing memory access patterns for anomalies indicative of heap corruption attacks.
This vulnerability aligns with Common Weakness Enumeration identifier CWE-416, which describes Use After Free conditions as a distinct category of software errors leading to security weaknesses. In the context of the MITRE ATT&CK framework, this exploit technique falls under Tactic Execution and specifically relates to techniques such as Command and Scripting Interpreter abuse or potentially Process Injection if the attacker leverages the code execution to spawn new processes within the browser's address space. Understanding these mappings helps in categorizing the threat landscape and prioritizing remediation efforts based on industry-standard taxonomies of software vulnerabilities. The resolution underscores the importance of rigorous memory safety practices in high-performance scripting engines like V8, where performance optimizations can sometimes introduce subtle timing-related bugs that are difficult to detect without specialized fuzzing tools or formal verification methods during development cycles.