Malicious PDF — malware analysis report

Static analysis result for SHA-256 5777f9f0a4adfb4d…

MALICIOUS

PDF

132.4 KB
MD5: e8a75ca42af20fe6ea4fe1c054b23b92 SHA-1: 9776c61b1e13637cda06cac9e4d9403601fc94c1 SHA-256: 5777f9f0a4adfb4de2d8de76922cff519dfe89f48f29dc1bc1a753c1a0a4b32a
258 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.001 Malicious Link/Object T1204.002 Malicious File

The PDF file contains embedded JavaScript that leverages multiple critical vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) in Adobe Reader. The heuristics indicate that the PDF launcher concatenates info fields, extracts characters at a fixed stride, and evaluates the result. An extracted artifact was also detected by ClamAV as Js.Exploit.Shellcode-18, suggesting the JavaScript is designed to download and execute a second-stage payload.

Heuristics 7

  • 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 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.
  • 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_obj0008_000.js
b61a30f38c09733d5fb5ba3f53d9d89015eca23aca42dc063c63d84526691e0e
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2095 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_000.js
3d78913bbabb6cfcbdc5636fcfb4473695cb164d520ca906cc0aedd65f646e72
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xA4A 14739 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).