Malicious PDF — malware analysis report

Static analysis result for SHA-256 35cb7ad50db6cd74…

MALICIOUS

PDF

5.8 KB Created: 2008-09-24 19:47:56 Authoring application: Adobe (via Notepad)
MD5: 9def0854cf5e7b92280fb9f6bdfe9c09 SHA-1: 76ec37f8239a4dc7a281b84693e4dcd20df71365 SHA-256: 35cb7ad50db6cd74f04bb3372ab5cbedbefc7de3dbd65536d03a9344b77eb2f3
358 Risk Score

Malware Insights

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

This PDF file contains multiple critical heuristic firings indicating exploitation of known Adobe Reader vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) via embedded JavaScript. The JavaScript is obfuscated but static analysis was able to deobfuscate and identify it as a malicious exploit stage. The primary intent appears to be downloading and executing a second-stage payload, as indicated by the ClamAV detection on extracted JavaScript artifacts. The file is detected as Pdf.Exploit.Agent-35931 by ClamAV.

Heuristics 9

  • 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-35931 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35931
  • 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.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (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.
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
36c12b7b33671918afdf82e8f586d6b5c7afe2342952890de7938e65245c2f5b
pdf-javascript-stream PDF /JS object 6 at offset 0x1343 931 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
ee2c247afc8629d0d19bcc440004217c945dd421902bbe075e42ca1451b0ef5f
deobfuscated-js metadata placeholder percent-decoded JavaScript at offset 0x16E 4881 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
3483e40a798f51c23f979fa2c4cc719be54ae17af43e4cc91f1e08abcdcbafe2
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x16E 4877 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).