Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7b4eca41dd44ef7…

MALICIOUS

PDF

9.8 KB
MD5: 435951b3f3624bf65f66b6150368aafa SHA-1: 7f597dd374a8752ee9a8a3c1f8dc2af40f185ed3 SHA-256: e7b4eca41dd44ef71736cfdda5505c7c70c5ca0cfa598a84d048a2fe633ec62a
126 Risk Score

Malware Insights

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

The PDF file contains a critical heuristic indicating the use of CVE-2007-5659, specifically leveraging the 'collab.collectEmailInfo' JavaScript function to execute a stager. This stager is designed to decode and evaluate obfuscated JavaScript, ultimately leading to the download and execution of a secondary payload. The presence of multiple JavaScript streams and deobfuscated scripts further supports this attack vector.

Heuristics 6

  • 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.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
9f17df95bc71874fe0f2dcb9f0e8f529cdb3604910d27079f2fbde52cabda2a8
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 256 bytes
annotation_subject_callee_hex_stage_000.js
414f0a6a953c1b04d420eb5a43cf2563886ed6f5c38ff5716b304300350ee494
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5299 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
a140efaf19fc1824618c687d56324eec90e7fe14e6456738fe3130037bf1b617
deobfuscated-js PDF JavaScript deobfuscation pass 44587 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).