Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bfa8acf92888170…

MALICIOUS

PDF

29.4 KB Created: 2008-07-26 19:43:58 Authoring application: Scribus 1.3.3.12 (via Scribus PDF Library 1.3.3.12)
MD5: 8c9cd56bda60831bc33506e6f315453e SHA-1: 099f16c385d44fe363b3078ca3bf327990fb640e SHA-256: 7bfa8acf92888170e4c6d71ea292870604e94e30da2b2c3bde88d8e4109e6449
388 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1059.007 JavaScript

This PDF file contains multiple critical heuristic firings indicating exploitation of known Adobe Reader vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992). The embedded JavaScript, decoded from quoted hexadecimal fragments, acts as a stager for an exploit. ClamAV detections further confirm its malicious nature as a PDF dropper. The primary attack vector is the exploitation of these vulnerabilities to deliver a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 9

  • 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)
  • ClamAV: Pdf.Dropper.Agent-5342589-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-5342589-0
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • 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.
  • 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.
  • 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_obj0013_000.js
d27f4855831a434dccb3dd6ce0dba43c3591a1c380a699206f46cf7118317361
pdf-javascript-stream PDF /JS object 13 at offset 0x336 28573 bytes
quoted_hex_fragment_stage_000.js
efe727fc8c4cb02c707e663dc92f8a8429c319830d0bbb9f569db5c9df559979
deobfuscated-js quoted-hex fragment decoded JavaScript object 13 at offset 0x409 5307 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).