Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0e9e1f36911b3db…

MALICIOUS

PDF

2.4 KB
MD5: 85cf567c10b5d2cfbe2f1e5ce069c7a7 SHA-1: 41ee881896540ca74a3569d690d3a4073bb6f6af SHA-256: f0e9e1f36911b3db840d76ecf5ac7dd53a61570332db2d94146f7eedc4c9a875
218 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes `eval()` and `unescape()` functions, indicative of obfuscation. The critical heuristic `CVE_2007_5659` specifically points to the exploitation of this CVE via the `Collab.collectEmailInfo` method, which is used to launch JavaScript. This script is designed to download and execute a secondary payload, as suggested by the presence of deobfuscated JavaScript and the ClamAV detection signature `Pdf.Exploit.Agent-35930`. The attack pattern involves luring the user into opening a malicious PDF that exploits a known vulnerability.

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-35930 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35930
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj111611_000.js
f23e505f155bfa9b9f356fa9fddf8d7fcafcc37fc2df3878e575e72c00c819d4
pdf-javascript-stream PDF /JS object 111611 at offset 0x899 697 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
fa91e1655aa831236f1f70df2458c1ad45240bda5a76b712f9ae102a99801a32
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 3902 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 6 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).