Malicious PDF — malware analysis report

Static analysis result for SHA-256 53f4cc571cafdf65…

MALICIOUS

PDF

11.8 KB
MD5: 0d717462c311afe7bc9b8df2ee20a240 SHA-1: b10849fa78a005066e9322beedff4bd7a6cceedc SHA-256: 53f4cc571cafdf657acfbf352e691b1d3e1951c79735d645d008486242c11ae4
186 Risk Score

Malware Insights

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

The PDF document contains embedded JavaScript that leverages the CVE-2007-5659 vulnerability, specifically using the Collab.collectEmailInfo method. The JavaScript is heavily obfuscated but appears to be a stager designed to download and execute further malicious content. The ClamAV detection also confirms its malicious nature. The document body itself is unreadable, so the rationale is based on the exploit and script behavior.

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: Pdf.Exploit.Agent-36088 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36088
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final 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_obj0007_000.js
9fd87306e37a04c361ea1b68a1cf4474b7a018e2270929a8c382cd129d8fc406
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 566 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
annotation_subject_callee_hex_stage_000.js
9cc528af0a38b1cc56e97feff6eb4977780fc44310d5c7eb05314e86fb0bf028
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5267 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).