CVE-2012-1436: Malware scanners bypassed by crafted EXE byte sequence

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 18 September 2026. Confidence: medium.

medium priorityThe flaw undermines malware detection across multiple AV products, but it requires a crafted file and medium attack complexity, and there is no confirmed in-the-wild exploitation or KEV listing.

What it is

The EXE file parser in several antivirus products (AhnLab V3 Internet Security, Emsisoft Anti-Malware, eSafe, Ikarus Virus Utilities T3, Panda Antivirus) fails to correctly handle an EXE file containing a \2D\6C\68 character sequence at a certain location. A remote attacker can craft a malicious executable that the scanner does not flag, defeating the core protection these products provide. The record notes the issue may later be split into separate CVEs if the parsers are shown to fail independently.

Impact

An attacker gains the ability to deliver malware that passes undetected through the affected scanners, leaving the endpoint's primary defense ineffective. The CVSS vector shows no confidentiality or availability impact, only a partial integrity impact.

Attack surface

Reached remotely over the network by supplying a crafted EXE file to the scanner; no authentication is required, though the CVSS vector notes medium attack complexity. No user interaction is specified in the record.

Exploitation

Not listed in CISA KEV and no reference tags indicate public exploit code, but EPSS is very high (0.93594, 99.8th percentile), suggesting elevated predicted exploitation activity. The record does not confirm in-the-wild use.

What to do

• Apply vendor updates for the affected antivirus products; the record does not list fixed versions, so confirm patched builds with each vendor.
• Layer detection with a second, independent scanning engine or endpoint detection tool so a single parser bypass does not leave the host unprotected.
• Block or quarantine executables from untrusted sources at the mail and web gateway rather than relying solely on endpoint AV.
• Monitor vendor advisories for the possible CVE split, which may require tracking separate fixes per product.

Detection

• Hunt for EXE files containing the \2D\6C\68 byte sequence at the parser-relevant offset and correlate with files that later execute or persist.
• Alert on executables that pass AV scanning but are subsequently flagged by a second engine or by behavioral EDR rules.
• Review AV scan logs for executables that were scanned without detection yet later spawned suspicious child processes or network connections.

This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.