Malicious PDF — malware analysis report

Static analysis result for SHA-256 f24a13455e1f5f6d…

MALICIOUS

PDF

61.3 KB
MD5: 8f11e76f0e9449c2a79682afeb25ecdf SHA-1: bbb1ad11de5b1b1a3c8daac97ccc0fd7f74ae9d0 SHA-256: f24a13455e1f5f6d91c1ec7062811d09d9566bf003e791dd1ad768068836da02
358 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: Malicious File T1059.001 Command and Scripting Interpreter: PowerShell T1059.003 Command and Scripting Interpreter: Windows Command Shell T1059.007 Command and Scripting Interpreter: JavaScript/TypeScript

The PDF file contains embedded JavaScript that utilizes character-table indexing for obfuscation, a technique commonly used to evade detection. Critical heuristics indicate exploitation of multiple CVEs (CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) related to JavaScript execution within Adobe Reader. The deobfuscated JavaScript likely serves as a stager to download and execute a secondary payload, as suggested by the 'eval_char_append_stage_000.js' filename and the heuristic 'PDF_JS_CHAR_TABLE_EVAL_STAGER'.

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-36310 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36310
  • 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
a7806c5f08e67c6fb000b88ea02000eabb7b20ca37d868fda3550b50f4e5dd54
pdf-javascript-stream PDF /JS object 76 at offset 0x2D4 54084 bytes
eval_char_append_stage_000.js
448047345a8752c3838c20ac91ff25330cb1e020360eef47571c8770771e583a
deobfuscated-js eval character-table append decoded JavaScript at offset 0x300 3870 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).