Malicious PDF — malware analysis report

Static analysis result for SHA-256 d316fd73fcf32b52…

MALICIOUS

PDF

11.9 KB
MD5: 530387196112e8475575177b3d7fb98d SHA-1: b1f49f867c02cbf509bca4cd9cf31e20c0c2d495 SHA-256: d316fd73fcf32b52582c63cd1e6a3f8737e3c856c0a43085928704dd3e1cf9b9
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 using the Collab.collectEmailInfo method. Static analysis recovered two deobfuscated JavaScript files, legacy_pdfkit_stage_000.js and legacy_pdfkit_stage_001.js, indicating a multi-stage attack. The primary function of the embedded script appears to be downloading and executing a secondary payload, consistent with a typical exploit kit delivery mechanism.

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
4b82422543b9219362d200165be36b039ba6d32e96516f1779aafcf11b51a1e3
deobfuscated-js z-percent hex-pair decoded JavaScript at offset 0x2E8 5059 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
808f3ecb9681446f7fff6ef235a8cc1398166446f757a21c4e12377be04e3cbd
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2E8 11996 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).