Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb21a07321897ebe…

MALICIOUS

PDF

3.5 KB Authoring application: rxode (via va)
MD5: 9f3e522f503fdacb2c8331f0550721e7 SHA-1: d917096fb369cef7e3b6e32910f45286890fc709 SHA-256: cb21a07321897ebe07f7ba3b1d2c93fe7425b3fc17b5b5339f40f07c939ec3cd
278 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell

The PDF file contains XFA (XML Forms Architecture) which is known to be a vector for exploiting older Adobe Reader vulnerabilities. Specifically, heuristics indicate exploitation of CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The XFA script decodes a hex string which likely contains further malicious JavaScript, designed to exploit these vulnerabilities for initial execution. No specific family could be identified, but the exploit chain is clear.

Heuristics 8

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • 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)
  • Embedded script payload in PDF stream medium PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • 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
embedded_file_obj0004.bin
a5514cca7a6632682f51c6ee1571050d836c0b68f15e78f2b4c7c31ddad114ae
pdf-embedded-file PDF EmbeddedFile object 4 at offset 0xDF 11196 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
xfa_hex_stage_000.js
81f666b0071209ccce8c11d3927e9aa73ea815816d32b2c25702d5858eb73963
deobfuscated-js XFA hex-decoded JavaScript (decompressed, direct) at offset 0x629 4807 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).