Malicious PDF — malware analysis report

Static analysis result for SHA-256 2555efbaf3bbd38f…

MALICIOUS

PDF

9.6 KB
MD5: abc1cec15a5a62b8d0d3c0ff37fddfbc SHA-1: 3a74a1d55395cce84738b2157d106130d3cb8b59 SHA-256: 2555efbaf3bbd38f81fdebcebce3491eebd366ce40a46819751e46643e08bd95
178 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages the CVE-2007-5659 vulnerability via the Collab.collectEmailInfo method. This exploit is designed to deobfuscate and execute JavaScript, which is then used to download and run a secondary payload. The presence of multiple deobfuscated JavaScript streams and the ClamAV detection strongly indicate malicious intent.

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-35905 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35905
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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.
  • 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
d8a6b4ad1abf04d0c4a4f89535cfb57f7312edef25c443f4e844c8ec9d0929dd
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 352 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
140da5c43885b78fd4977fd3683e91cd8995b06e98e9a6b53274180de4712a20
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 12270 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
d6992f5941591c570112ec80147c35b0648dea9134052802e38f15bf499dc800
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 5205 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).