Malicious PDF — malware analysis report

Static analysis result for SHA-256 d61486f2558ec2ef…

MALICIOUS

PDF

83.6 KB
MD5: 42e29be4f2cfc21dc4d039e713ba14d7 SHA-1: 69f928db9ab70d8cedafd3899bdf13b42fbd9632 SHA-256: d61486f2558ec2efd341c7ec7d3d5a1104021c3951dabdc93b90ced56e79d168
456 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes a character table to obfuscate its content, a common technique for delivering exploits. Critical heuristics indicate the exploitation of several CVEs related to PDF JavaScript execution, including media.newPlayer, Collab.getIcon, Collab.collectEmailInfo, and util.printf. The extracted JavaScript streams and the ClamAV detection (Js.Exploit.HTML-29) confirm the malicious nature of the file, likely serving as a downloader or initial exploit stage.

Heuristics 10

  • 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: Js.Exploit.HTML-29 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Js.Exploit.HTML-29
  • 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.
  • 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.
  • 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.
  • 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_obj0076_000.js
dbf1efe6fe41e7f5d7a4722f6c9275de7e415554e437db9529e7bb79171ad472
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 84728 bytes
Detection
ClamAV: Js.Exploit.HTML-29
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
char_table_stage_000.js
0714a063ad5c9cf078ea51554a90c282dbdfd6628417593fb084e906c04c883d
deobfuscated-js char-table indexed JavaScript (PDF /JS object 76) at offset 0x2FB 3858 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).