Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4e9bacc8d5d9d01…

MALICIOUS

PDF

3.6 KB Created: 2008-31-20 53:85:00 Authoring application: Scribus 1.3.3.12 (via Scribus PDF Library 1.3.3.12)
MD5: 09333e99a6a1e1d10fdc6fdfe18ee30e SHA-1: 522cadc27e2b6ead1a33aa2da080112189dd5c2e SHA-256: a4e9bacc8d5d9d0121436db1de84cb99ee66c0348b04e3a9cd7468c19d958db0
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file contains embedded JavaScript triggered by the OpenAction, which is a common technique for exploiting PDF reader vulnerabilities. The critical CVE-2007-5659 heuristic indicates the use of a specific exploit involving `Collab.collectEmailInfo` and `eval()` with decoded JavaScript. This script is designed to download and execute a second-stage payload. The obfuscated nature of the script and the use of `String.fromCharCode` suggest an attempt to evade detection.

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)
  • OpenAction trigger high PDF_OPENACTION
    PDF has an /OpenAction — code runs automatically when opened
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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_obj0013_001.js
c20dc604ad90fdcb83d0ed4970bc6480c617c7041bba615bd76004420edfff4c
pdf-javascript-stream PDF /JS object 13 at offset 0x3D7 14049 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
numeric_charcode_stage_000.js
845f8050071e0902125576bd79cc99cda36b146e2b9f2b498092db2a6cf360b1
deobfuscated-js numeric char-code string decoded JavaScript at offset 0x445 4272 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).