Malicious PDF — malware analysis report

Static analysis result for SHA-256 e994ecdce7137f65…

MALICIOUS

PDF

127.9 KB
MD5: bd7e322aab70a3c995e3abcbdd4a8952 SHA-1: 5d5cae9448841e336d5dfedf16fe81857e49f8e0 SHA-256: e994ecdce7137f6572a7d4c70b01b34eae959fc1042815c57059c4c310f9c55d
318 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript that leverages multiple known vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) through the use of `Collab.getIcon`, `Collab.collectEmailInfo`, and `util.printf` functions. The heuristics indicate that the PDF launcher concatenates information fields, extracts characters at a fixed stride, and evaluates the result. An extracted and deobfuscated JavaScript file (`legacy_pdfkit_stage_000.js`) was also detected, suggesting a multi-stage attack. The primary intent appears to be the execution of arbitrary code, likely to download and run a second-stage payload.

Heuristics 8

  • 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-36307 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36307
  • 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
0414b644a32259a9d046a9be8b78b88c5cc8262d8add6fa9ee35c363385c8642
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 3243 bytes
Detection
ClamAV: Pdf.Exploit.Agent-36307
Obfuscation or payload: unlikely
legacy_pdfkit_stage_000.js
f5f15d4c1f190b022aa9e4777340d6960f04d8544df589ab19bfa9b09b5e93d7
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xEC6 6042 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s).