Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c7f668b66df891…

MALICIOUS

PDF

12.0 KB
MD5: 49f9cf4965c7cb98a2f9a84fdb63995a SHA-1: bc57abb9ccec10d93e730c1cb32dd2a5f95ef05d SHA-256: b3c7f668b66df89161602e70190c5e632b61310846bb62a57eb8ae6bdabd92eb
416 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell T1059.007 JavaScript

The PDF file contains embedded JavaScript that is heavily obfuscated and designed to exploit multiple Adobe Reader vulnerabilities. The heuristics indicate that this JavaScript is decoded from a split character-table join and is likely responsible for executing a second-stage payload. ClamAV detections confirm the malicious nature of the embedded script.

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: Js.Exploit.HTML-28 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Js.Exploit.HTML-28
  • 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.
  • 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
66c5837ee2c3d89851cfaee3094673445c2766c4fc84f1aec02bd75fea890cba
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 11370 bytes
Detection
ClamAV: Js.Exploit.HTML-28
Obfuscation or payload: unlikely
split_char_table_stage_000.js
e06d2e3f83f581556c75b25ffcc857e7e82c3336beb582b31bf7c33777f41f8d
deobfuscated-js split character-table join decoded JavaScript at offset 0x2D1 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).