Malicious PDF — malware analysis report

Static analysis result for SHA-256 a151d9e0321ae2ee…

MALICIOUS

PDF

12.1 KB
MD5: d29caefe575fff262a8d359b0648b772 SHA-1: 30a7a4457e83cd61ad378c8dea6a1037abb16d5f SHA-256: a151d9e0321ae2eea5a21a4dee609839c05cced12995425dd79b4cfbda0f1490
118 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is obfuscated and appears to be a stager. The critical heuristic CVE_2007_5659 indicates exploitation of a known Adobe Reader vulnerability (Collab.collectEmailInfo) to execute this JavaScript. The deobfuscated JavaScript is large and likely responsible for downloading and executing a secondary payload, which is a common technique for initial access.

Heuristics 5

  • 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)
  • 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.
  • 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
0df291d69669aabea8d48539ff6e3447b14e49a861871000e6476334f075bd19
pdf-javascript-stream PDF /JS object 7 at offset 0x1A6 1011 bytes
annotation_subject_callee_hex_stage_000.js
b5ee804f07d4de1ae511c1874dcdf90fd93777634be6a2cfdb3b7a25406b7d3a
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14F 4923 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).