Malicious PDF — malware analysis report

Static analysis result for SHA-256 1e5e3c3a22e52644…

MALICIOUS

PDF

11.5 KB
MD5: 59abd3461f1c60313404f2a8978c8861 SHA-1: a5f3ac8a6b3703e8fef50ec5194ed7d8c538c7c4 SHA-256: 1e5e3c3a22e52644c156d75ef111d695c06b21d3060f44913fbeb5f1053d63aa
146 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages the CVE-2007-5659 vulnerability, specifically targeting the Collab.collectEmailInfo function. Static analysis recovered two deobfuscated JavaScript files, 'legacy_pdfkit_stage_000.js' and 'legacy_pdfkit_stage_001.js', which likely contain the malicious payload. The primary function of this exploit appears to be the download and execution of further malicious code.

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
84f899e11569114afbd6f2fc3b25e60e5cbbfcee327abeb167a06f192376a7a8
deobfuscated-js z-percent hex-pair decoded JavaScript at offset 0x2E8 4860 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
8651f7a4f43931c23fcf35b4ff31268eab665d2a2ab9b76ea2a527825d99d8a8
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2E8 11719 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).