Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c4f7d6ec231796c…

MALICIOUS

PDF

12.4 KB
MD5: 70a335bd483be4d21d1253cae2546c2a SHA-1: b9899b1ff95de570440de4a2c55b40502cf6a9b7 SHA-256: 8c4f7d6ec231796c7c44f772d466005cf80060416e48f00700c159b3243cff8c
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 that is obfuscated and then decoded using a hex decoder keyed by callee.toString(). This JavaScript is designed to exploit CVE-2007-5659, a vulnerability in Adobe Reader related to the `Collab.collectEmailInfo` function. The primary purpose appears to be downloading and executing a second-stage payload, as indicated by the ClamAV detection signature 'Pdf.Exploit.Agent-36063'.

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
0184c1f1e4b156403a3fd8145760e67cfeb478c326edbe55ff66f70174ac0423
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5314 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
1a231fb02afede0b96bc739ae991467a34d1e8f9b55ca9e5827f0f847cd0b18c
deobfuscated-js PDF JavaScript deobfuscation pass 79365 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).