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Mallory
HighCISA KEVExploited in the wildPublic exploit

Out-of-bounds read in Google V8 Array.prototype.concat

IdentifiersCVE-2016-1646CWE-125· Out-of-bounds Read

CVE-2016-1646 is an out-of-bounds read vulnerability in the Array.prototype.concat implementation in Google V8, specifically in builtins.cc, as used by Google Chrome before 49.0.2623.108. The flaw stems from improper handling of element data types during concat operations. A remote attacker can trigger the bug by supplying crafted JavaScript that causes V8 to incorrectly process array element representations, leading to an out-of-bounds memory read. The published description notes denial of service as a demonstrated outcome and leaves open the possibility of additional unspecified impact.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can crash the browser process, resulting in denial of service. Because the flaw is an out-of-bounds read in a JavaScript engine, it may also expose adjacent memory contents or enable other unintended effects depending on exploitability in the target environment, although the provided content does not confirm information disclosure or code execution for this CVE.

Mitigation

If you can’t patch tonight, do this now.

Until patching is completed, reduce exposure by restricting access to untrusted web content, disabling or limiting use of vulnerable Chromium-based browsers or embedded webviews where feasible, and applying enterprise controls such as URL filtering, application isolation, and rapid browser update enforcement. Because exploitation is delivered via crafted JavaScript in web content, sandboxing and site isolation may reduce impact but do not replace patching.

Remediation

Patch, then assume compromise.

Upgrade Google Chrome to 49.0.2623.108 or later. More generally, update any affected Chromium/V8-based application to a version containing the fix for CVE-2016-1646. Ensure embedded or repackaged Chromium components in downstream applications are also updated, as exploit frameworks have targeted vulnerable Chromium-based browsers and embedded browser components.
PUBLIC EXPLOITS

Exploits

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VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
CanonicalUbuntu Linuxapplication
DebianDebian Linuxoperating_system
GoogleChromeapplication
OpensuseLeapoperating_system
OpensuseOpensuseoperating_system
Red HatEnterprise Linux Desktopoperating_system
Red HatEnterprise Linux Eusoperating_system
Red HatEnterprise Linux Serveroperating_system
Red HatEnterprise Linux Workstationoperating_system
SusePackage Hubapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

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Exposure mapping

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Threat actor evidence3

Every observed campaign linking this CVE to a named adversary.

Associated malware5

Malware families riding this exploit, with evidence and IOCs.

Detection signatures1

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity

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