Malicious PDF — malware analysis report

Static analysis result for SHA-256 691952cc9fa9847f…

MALICIOUS

PDF

4.4 KB Created: 2009-07-09 28:29:52 +03:00 Authoring application: fackoPDF 6.06 (via BCL macroPDF 7.07)
MD5: ea48de4d4bfb3342756c7bb2ef8b3694 SHA-1: a7297fbb1a2074aa4ebed6b44a8139f34c438354 SHA-256: 691952cc9fa9847f40bc180b3c46317a689c64920fb02419aaebe06eafc91759
372 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that exploits multiple known vulnerabilities in Adobe Reader, specifically CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The JavaScript is heavily obfuscated but ultimately decodes to a stager that downloads a second-stage payload from the URL http://bigmig.org/unp/getexe.php. This indicates a clear intent to exploit the user's system and download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 11

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
  • 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)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
  • Pidief-style multi-CVE JavaScript dispatcher critical CVE likely PDF_PIDIEF_MULTI_CVE_DISPATCH
    A single JavaScript body branches on app.viewerVersion and invokes two or more of the canonical Reader sinks (Collab.collectEmailInfo, Collab.getIcon, util.printf with a field-width format string). This is the 2009-2010 Pidief.J multi-exploit landing template: a per-version dispatcher that fires the matching CVE chain for whichever Reader version opens the file.
  • Quoted-hex fragment JavaScript stager high PDF_QUOTED_HEX_FRAGMENT_JS_STAGER
    PDF JavaScript stores the hidden exploit stage as many quoted hexadecimal fragments, joins them through helper functions, and evals the recovered JavaScript. The decoder is bounded and only fires when the recovered stage contains concrete Acrobat exploit APIs or heap-spray shellcode markers.
  • PDF JavaScript shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF JavaScript shellcode contains a hardcoded http(s) URL stored as little-endian %uXXXX Unicode escapes. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • 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.
  • PDF paints image(s) but contains no text operators info PDF_IMAGE_ONLY_LURE
    PDF has 1 image XObject(s) and the content stream contains no text-emitting operators (BT/ET, Tj, TJ, ', ") in either raw bytes or decompressed streams — this is the screenshot-as-PDF pattern used to bypass text-based scanners and to deliver instructions purely through rendered pixels. It is informational unless paired with invisible links or risky URI context.
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://bigmig.org/unp/getexe.php

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0015_000.js
91bfddc0ff40391f333320f5f5a16fb436e49fd162bd45c28282625d7a3ac4f4
pdf-javascript-stream PDF /JS object 15 at offset 0x317 9036 bytes
quoted_hex_fragment_stage_000.js
a9c43503860e4f6442f3ad6a2e0dddc5770bc20779a7cf9e20a6db4a3254c3b3
deobfuscated-js quoted-hex fragment decoded JavaScript object 15 at offset 0x3F1 3292 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).