Malicious PDF — malware analysis report

Static analysis result for SHA-256 942a67bb33e30441…

MALICIOUS

PDF

5.9 KB Created: 2008-09-24 19:47:56 Authoring application: Adobe (via Notepad)
MD5: 11c9acfe2102ef2c6b54969f003742e4 SHA-1: 18c39646fdbd1f579ee6397a56dd5bac6b7d3e66 SHA-256: 942a67bb33e3044150f523d2c7021ed45c6aee10a7ab8849bad64f7bc4f4ba67
358 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages multiple known Adobe Reader vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) to achieve code execution. The critical heuristics indicate that the embedded JavaScript, specifically the 'eval()' call and the use of Acrobat JavaScript API sinks, is designed to exploit these CVEs. The extracted JavaScript artifacts, 'legacy_pdfkit_stage_000.js' and 'legacy_pdfkit_stage_001.js', are likely responsible for downloading and executing a subsequent payload, as suggested by the ClamAV detection of 'Js.Exploit.Shellcode-18'.

Heuristics 9

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
  • 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)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-35931 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35931
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (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_obj0006_000.js
e0f6902f1862a6a5f58457324389789bde79447bf3480d71124a638a748123bd
pdf-javascript-stream PDF /JS object 6 at offset 0x1389 981 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
de76bf0c98f014e6f9a0ddf3ad28f67107d8f5011691e977956f92335982a43c
deobfuscated-js metadata placeholder percent-decoded JavaScript at offset 0x16E 4971 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
87b3a94efca9ed977565c73ab8053429f6731043a18c9bebffa26862dc9fcbae
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x16E 4967 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).