Malicious PDF — malware analysis report

Static analysis result for SHA-256 37e1105a80531db6…

MALICIOUS

PDF

13.2 KB
MD5: 842f4c00104c8031f6fffae174e12426 SHA-1: 577b4912d47fe0c33064f93b75c3a00b26240310 SHA-256: 37e1105a80531db6bf69b80a39c2fee055478d83af7eaa685b19877bbd38424f
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF file contains obfuscated JavaScript that exploits CVE-2007-5659, specifically targeting the Collab.collectEmailInfo function in Adobe Reader. This exploit is designed to download and execute a second-stage payload. The presence of binary-XOR encoding and string manipulation within the JavaScript indicates a deliberate attempt to evade detection. The file is classified as malicious due to this exploit.

Heuristics 7

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Heuristics.PDF.ObfuscatedNameObject critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Heuristics.PDF.ObfuscatedNameObject
  • Binary-XOR JavaScript stager high PDF_BINARY_XOR_JS_STAGER
    PDF JavaScript stores viewer-version payload branches as long binary digit strings, XORs each bit pair, converts 8-bit chunks with String.fromCharCode, and evals the recovered exploit stage.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0049_000.js
08aafd45656a531f6393dc4508e5385db374361a8c0197c3ed1f01d2dc28acc5
pdf-javascript-stream PDF /JS object 49 at offset 0xA 78844 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 6 long base64-like blob(s).
binary_xor_stage_000.js
c1d0b40f07e054d1db24581f00b7eeec28d48f6fbe241be1cc149f33d34baa19
deobfuscated-js binary-XOR decoded JavaScript at offset 0x3F8 1318 bytes