Malicious PDF — malware analysis report

Static analysis result for SHA-256 acf36a3ddd82589d…

MALICIOUS

PDF

11.6 KB
MD5: 9a0aec142d4024bfdf77d4b920860f60 SHA-1: dbf3b17b5b3fad406e52e8f3e58b5926ad688c87 SHA-256: acf36a3ddd82589d64baeedef696bd188c8e333fd3f42ea0f41f0afeaa29e30a
186 Risk Score

Malware Insights

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

The sample is a PDF file that leverages the CVE-2007-5659 vulnerability through the `collab.collectEmailInfo` function to execute embedded JavaScript. The JavaScript is heavily obfuscated, but analysis indicates it acts as a stager, likely downloading and executing a second-stage payload. The presence of multiple JavaScript streams and the specific exploit technique point to a malicious PDF designed for exploitation.

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
a01122c2e6f639eba8736843bd02911776fafa27f474516f7c9fb95d2cdae723
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 4922 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
14807fb9062312b81506f2ced0d4b16c8b9596303cb40a9f14e8f28513fb6b0f
deobfuscated-js PDF JavaScript deobfuscation pass 70678 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).