Malicious PDF — malware analysis report

Static analysis result for SHA-256 db4673715c00b3d0…

MALICIOUS

PDF

12.0 KB
MD5: 06e314835bcdea9177d04426fdc2a218 SHA-1: b4fc026a6bce7cc39989f5ab390019678859d5c5 SHA-256: db4673715c00b3d01081d7a95170455236a8c12d0d5e3b6bcca4b7b627df9312
186 Risk Score

Malware Insights

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

The file is a PDF containing embedded JavaScript, identified as malicious by ClamAV (Pdf.Exploit.Agent-36063). The critical heuristic CVE_2007_5659 indicates the exploitation of a known vulnerability using a JavaScript stager embedded within an annotation subject. This stager likely decodes and executes further malicious JavaScript, as evidenced by the extracted deobfuscated.js file. The primary attack vector appears to be leveraging the 'collab.collectEmailInfo' function to trigger the exploit.

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
478c1932d34930290420dcd8e9ae0f417d99eb547dd2b8cd25a299ca9383c933
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5137 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
8ccfbae8146943777ee5f8c67804736600d85b1cfb1fdd5c1813fa8bed46f227
deobfuscated-js PDF JavaScript deobfuscation pass 79055 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).