Malicious PDF — malware analysis report

Static analysis result for SHA-256 b63e5e418edeaff4…

MALICIOUS

PDF

76.7 KB Created: 2009-12-18 19:42:29 Authoring application: PDF Library 6.3.5 (via PDF Library 6.7.3)
MD5: 14736558eff4d194573a5859c1f81e80 SHA-1: 7d32e162f553b3d7b2c32dff1291d51bf5beec77 SHA-256: b63e5e418edeaff47e08597e44e3250eb6d2a24a07e168ee323d96827de90a1f
340 Risk Score

Malware Insights

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

The PDF exploits multiple critical vulnerabilities in Adobe Reader, specifically targeting Collab.getIcon, Collab.collectEmailInfo, and util.printf functions. Static analysis recovered a deobfuscated JavaScript file, 'legacy_pdfkit_stage_000.js', which likely contains the second-stage payload. The presence of ClamAV detections for 'Pdf.Exploit.Agent-36110' and 'Js.Exploit.Shellcode-18' further confirms the malicious nature of the file and its embedded script.

Heuristics 10

  • 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-36110 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36110
  • 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.
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PSSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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
b953393f88a400ea0433c90c6c162788835849b32c34854c67f09f2d30cbd654
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 38779 bytes
legacy_pdfkit_stage_000.js
2d14698a88312d99f11059c05f2c12c477ae0326e0335ca6ed78b960f9394ffa
deobfuscated-js numeric array subtract-key decoded JavaScript at offset 0x1A5 10018 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).