Malicious PDF — malware analysis report

Static analysis result for SHA-256 a56460ba4aae9dd2…

MALICIOUS

PDF

11.7 KB Created: 2009-11-24 19:45:82 Authoring application: PDF Library 1.6.9 (via PDF Library 3.9.7)
MD5: 033c1b39762daa0e354b5246ff69b454 SHA-1: eef6bf20ad95c6a0c5c66bac1042474c6da5c0d8 SHA-256: a56460ba4aae9dd24d44be809eedac1c706e5357318c389bc547702b3122ad0a
278 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.001 Malicious Link/Object T1071.001 Web Protocols

This PDF document exploits multiple known Adobe Reader vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) through embedded JavaScript. The JavaScript, identified as legacy_pdfkit_stage_000.js, is heavily obfuscated but static analysis indicates it likely downloads and executes a second-stage payload, as suggested by the ClamAV detection 'Js.Exploit.Shellcode-18'. The use of multiple CVEs and obfuscated JavaScript points to a sophisticated exploit kit.

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 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.
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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_obj0007_000.js
e82598578c65e506d92b79f61f45e5b2997070651a881b1516e339f291f988a6
pdf-javascript-stream PDF /JS object 7 at offset 0x268 37349 bytes
legacy_pdfkit_stage_000.js
9b5aa5b683d085885dd23cb8457ae0fa735d50ec360cef6e6b8c4b31038d43a1
deobfuscated-js numeric array subtract-key decoded JavaScript at offset 0x268 9880 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).