Malicious PDF — malware analysis report

Static analysis result for SHA-256 543d7ddc57920809…

MALICIOUS

PDF

12.2 KB
MD5: 295937d6ae68b1733eb1ca31cdffb59c SHA-1: 676938b20e106cd0acab85b33d4ffed0c6e5375f SHA-256: 543d7ddc57920809e3445b0a2ff821a83e0aa4d03425bad32c2d5d59c83c6bf6
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious Link/URL

The PDF file contains embedded JavaScript, specifically leveraging the CVE-2007-5659 vulnerability through the `collab.collectEmailInfo` method. This JavaScript is heavily obfuscated and appears to be a stager, indicated by the heuristic `PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER`. The primary function of this script is to decode and execute further malicious code, likely downloading and running a second-stage payload. The ClamAV detection `Pdf.Exploit.Agent-36063` further confirms its malicious nature.

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 3

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
50c3cce1634087667eeb6797b601fb397c84317377a84f86d866eef2c8d69ee0
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5178 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
ca79cafba297d7fe9c410889531ede1370a92fca7294a9b798973bcb49022e97
deobfuscated-js PDF JavaScript deobfuscation pass 78612 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).