Malicious PDF — malware analysis report

Static analysis result for SHA-256 a65478f4c45f5817…

MALICIOUS

PDF

11.3 KB
MD5: 130b21b932a64ddb86aaea8f6d3fafee SHA-1: 95c60873e9661faf8fb0156fbdfc5de2dc10374a SHA-256: a65478f4c45f58170f4c621f0bc7625f511eea64aa9c4f47ae8c9a5f7cd743e2
118 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, identified by the PDF_JAVASCRIPT and PDF_JS heuristics. A critical heuristic, CVE_2007_5659, indicates the use of Collab.collectEmailInfo to decode and execute a hex-encoded JavaScript stager. This stager is responsible for downloading and executing a second-stage payload, which is a common technique for initial access and further infection. The obfuscated nature of the script and the use of a known PDF exploit contribute to the assessment.

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
3f87fb6acf968e39b6cc0d180ce87d5dcd4d859153eb9c295ffaa2659946682f
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 4916 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).