Malicious PDF — malware analysis report

Static analysis result for SHA-256 28cb9e8b2e9b2492…

MALICIOUS

PDF

5.8 KB Created: 2008-09-24 19:47:56 Authoring application: Adobe (via Notepad)
MD5: fde83fee298e6138354b9d3e8e03d6ee SHA-1: f47ad78e4287d052580fd3b89f0eb6e4063f50cb SHA-256: 28cb9e8b2e9b24922a5df17ff2f575d2770f91137d49aa2a6269de22f3a0cd9f
358 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages multiple known Adobe Reader vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) via `eval()` calls. Static analysis indicates that these exploits are used to execute a secondary stage payload, as evidenced by the ClamAV detection of a JavaScript exploit shellcode. The extracted JavaScript files are heavily obfuscated, but the presence of these exploit triggers strongly suggests a malicious intent to compromise the user's system.

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
cc210305a966f4899ec1b52f90c950e29d6d5766a6c8e431b55753f299b8d707
pdf-javascript-stream PDF /JS object 6 at offset 0x1366 906 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
088336f7cda5c5f7315715bc6faa6672752702f099216cc032001016c9ce5534
deobfuscated-js metadata placeholder percent-decoded JavaScript at offset 0x16E 4917 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
f2f02cfa3f771369e1d8ec561912f65d394148f4535892ae5c4d3de5dde77c7c
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x16E 4913 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).