Malicious PDF — malware analysis report

Static analysis result for SHA-256 4744b9dc66f04df6…

MALICIOUS

PDF

7.7 KB
MD5: 45784fe67d921465f68ad220dc4d3e16 SHA-1: 3d15e145c8711a4f3dc54f98269b6af3c21dc7e5 SHA-256: 4744b9dc66f04df662b37e2c6a9e6d9e81a02bb49198a6ebb19389f3b1668088
456 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is heavily obfuscated and uses custom Base64 decoding. This script exploits multiple Adobe Reader vulnerabilities, specifically CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992, to execute a malicious payload. The ClamAV detection 'Pdf.Dropper.Agent-1828714' and the analysis of the extracted JavaScript confirm its role as a dropper for further malicious stages.

Heuristics 11

  • 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.Dropper.Agent-1828714 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-1828714
  • 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.
  • OpenAction trigger high PDF_OPENACTION
    PDF has an /OpenAction — code runs automatically when opened
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Suspicious extracted artifact high 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.
  • String.fromCharCode medium PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically (matched inside decoded stream)
  • 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.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0009_000.js
12c4b3fe8f3811567652210ac3e61eccddc9cb5e83176b9ac56236784c3243f9
pdf-javascript-stream PDF /JS object 9 at offset 0xD6 19772 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
custom_b64_stage_000.js
77d8d5da7378b1068caefcc40a7756d1744e571c37801fdf21b9595ab6b8261f
deobfuscated-js custom Base64 decoded JavaScript layer 2 (PDF /JS object 9) at offset 0x450 10598 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).