Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1bd317dd5377f01…

MALICIOUS

PDF

11.7 KB
MD5: 404438e890152b8582e1f2d35515b31b SHA-1: f96b5d0e92f590bc750907c9779b61423f015dd5 SHA-256: e1bd317dd5377f01f7f98fe2f891852ef969583e3e6b9727ea37d1b443d4d26d
118 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, triggered by the 'Collab.collectEmailInfo' method, which is a known vulnerability (CVE-2007-5659). This JavaScript acts as a stager, decoding a hex-encoded payload. The recovered JavaScript is heavily obfuscated, but the heuristic indicates it's designed to download and execute a second-stage payload. The presence of multiple JavaScript streams and the specific exploit technique point to a malicious PDF designed for initial payload delivery.

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
e53cd3b2abe44a0ffe069bd2e56f48e1b1e8932489ba93331de44d133ee7058e
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 582 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
d09de009de5e2e9b3f314df97a1299aea781ab96744a5eb134031f527e30d1e6
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5114 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).