Malicious PDF — malware analysis report

Static analysis result for SHA-256 e21f431ed52439af…

MALICIOUS

PDF

12.1 KB
MD5: 5f522ffa257cbf85491b3f17e4edf03c SHA-1: b922693e80b38cc67ce045d0a59af229b3be9eaf SHA-256: e21f431ed52439af63e47834f70ee3fb26d5b061ea008eb366c8043504aeccf0
146 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that exploits CVE-2007-5659, specifically targeting the Collab.collectEmailInfo function. The heuristic firings indicate that this JavaScript is designed to download and execute a second-stage payload, as evidenced by the extraction of two deobfuscated JavaScript files, 'legacy_pdfkit_stage_000.js' and 'legacy_pdfkit_stage_001.js'. These scripts likely facilitate the download and execution of further malicious content.

Heuristics 6

  • 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-35903 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35903
  • 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
860eae5f96eb426380281c575a089242b50523bbb4bbb8dd765e582cd9c07d2e
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 294 bytes
legacy_pdfkit_stage_000.js
0e1a7867c8a2a205ee3a5059b19fd006061e8ec5d862f955d114b250109acccd
deobfuscated-js z-percent hex-pair decoded JavaScript at offset 0x2E8 5140 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
e7363ecae7d74d16b34f2f863df2be3dd3802beef7f32c80cc7da25a8bec9468
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2E8 12271 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).