Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a79058ccd606acc…

MALICIOUS

PDF

13.2 KB
MD5: d1ad4b3e1c18b06dbc6c0ff34f224fa7 SHA-1: a55baa83fe3cb775f53b19ea587116ef79238c4c SHA-256: 0a79058ccd606acc6cff10314d794e6b3a4bf6d18ac4b56b50170fe1a5cc95c2
276 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains obfuscated JavaScript that exploits CVE-2007-5659 (Collab.collectEmailInfo). The script is designed to download and execute a second-stage payload from a hardcoded URL. The deobfuscated JavaScript reveals the URL 'http://mordor.stats.mo.com/d/mld.php?f=26052&t=20&r=6520', which is likely used to fetch the next stage of the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 8

  • 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)
  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • 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
8a423ff23411a7aa3e889256607d7a7272a94b071ff0cbc44fcba66f3d35219f
pdf-javascript-stream PDF /JS object 49 at offset 0xA 78556 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
4fd1de754d5cbfb13325d7f641b85a861dd4e60a490ccd6733c27a708ccefc92
deobfuscated-js binary-XOR decoded JavaScript at offset 0x3F8 1312 bytes