Malicious PDF — malware analysis report

Static analysis result for SHA-256 ed7592a67acf3c5e…

MALICIOUS

PDF

12.2 KB
MD5: df48213a8c80fd094d13623f22cee327 SHA-1: fdb5f46dc167751c9cd463a2447595df3e2f65f7 SHA-256: ed7592a67acf3c5e20ac255be4357d1b384ac9d89c31de9b8f5cbb7bb9ec70a4
186 Risk Score

Malware Insights

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

The sample is a PDF file that leverages the CVE-2007-5659 vulnerability, specifically using the Collab.collectEmailInfo method to execute embedded JavaScript. This JavaScript is heavily obfuscated but appears to function as a stager, likely responsible for downloading and executing a secondary payload. The ClamAV detection of 'Pdf.Exploit.Agent-36063' further supports 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 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
c2972493dfe764d3011b1d688f86d8a4bfaa7446f25f48f9cf417efc197f0c7c
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5242 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
325eae2c13e92c63963983319056f5c7f576f91ff2f98ff8f62a382b7a7ddd08
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12351 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
8f57f1746d5a834a763e17833a513f8ea4975dd4b5111ccda6a60e98736e2cbd
deobfuscated-js PDF JavaScript deobfuscation pass 74509 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).