Malicious PDF — malware analysis report

Static analysis result for SHA-256 e785b4221896c332…

MALICIOUS

PDF

11.9 KB
MD5: 37455981a26a7289a1864e54f8dc854d SHA-1: bc4fe4a0bca89d37c5d304285de06a7792adb649 SHA-256: e785b4221896c3321f54c76f7b96e7240b8587da48d46f8ee3290a943e26a906
186 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, specifically leveraging the CVE-2007-5659 vulnerability through the 'collab.collectEmailInfo' function. This JavaScript is heavily obfuscated and appears to be a stager, indicated by the heuristic 'PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER'. The deobfuscated JavaScript is substantial, suggesting it performs complex actions such as downloading and executing further payloads. The presence of multiple JavaScript artifacts and the critical ClamAV detection strongly indicate malicious intent.

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
659640731a0b8bed6c4ec038c023b080fdf58d4b056711b72cbe3fdaf72cf3b3
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5035 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
2e8404a34dfd33fc1f628a1fd0e304c48df35d66ac65082f5c2fb17403ce4f53
deobfuscated-js PDF JavaScript deobfuscation pass 72895 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).