Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1bbcd2a3f48ef1f…

MALICIOUS

PDF

106.8 KB
MD5: e85eba67f8e8f2e1f52fe65bff11e7c5 SHA-1: 141ab6e5e7a8e33516d1a8df174412e0485b4ce8 SHA-256: c1bbcd2a3f48ef1fec954e24eaccdb7574f37d9df4748e2e812d6182c2019c37
360 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes character-table indexing to obfuscate its malicious payload. This JavaScript leverages several critical CVEs (CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) to achieve code execution. The primary function of the script appears to be downloading and executing a second-stage payload, as indicated by the 'Agent' detection name from ClamAV.

Heuristics 9

  • 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)
  • ClamAV: Pdf.Exploit.Agent-36749 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36749
  • Character-table JavaScript eval stager high PDF_JS_CHAR_TABLE_EVAL_STAGER
    PDF JavaScript reconstructs an exploit stage by indexing into a small character table, appending hundreds of one-character fragments, joining the array, and evaluating the result. This static fallback fires only after the bounded decoder recovers an exploit-like stage, so it catches this obfuscation even when no single CVE API signature is available.
  • 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_obj0076_000.js
dde8fe78350b291950d284639e2e814558e9470f13af203d0f4df1a0a2846c1b
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 108496 bytes
char_table_stage_000.js
b2941c94f7909e1b35032784b48a1bf3dd35810d18729793fcebc72e1f65ce3a
deobfuscated-js char-table indexed JavaScript (PDF /JS object 76) at offset 0x2F1 3894 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).