Malicious PDF — malware analysis report

Static analysis result for SHA-256 bdc3b9675f1a0d1b…

MALICIOUS

PDF

12.0 KB
MD5: b04a22428bbc08f0e0bb1f0b85654ae1 SHA-1: 861b77e452b155539bc936c5d33f77c634316276 SHA-256: bdc3b9675f1a0d1bd4b6aa80e6947942b5cbfff5c1e37a8bada75642c75605be
186 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is obfuscated and designed to be executed via the CVE-2007-5659 vulnerability, specifically using the 'collab.collectEmailInfo' method. This JavaScript acts as a stager, indicated by the presence of multiple deobfuscated JavaScript files extracted during analysis. The primary function appears to be the execution of further malicious code, likely downloading and running additional payloads.

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-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
a9fe27401f1a3735002ef8f7519cdfd2f2579a44db24cceed245d8437f0c2590
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5126 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
03227a9d96d3272383b2c5a379ea8d65e9ce920e1fea01ddd1f01589667baa19
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12105 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
f3320d8ae5e33fc554a71d36102ab45e43d89c89cc6a0ca9fa149f172ab17428
deobfuscated-js PDF JavaScript deobfuscation pass 72148 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).