Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdb2c3e6eae09b50…

MALICIOUS

PDF

299.6 KB
MD5: 4898fb2bdc73eed428fe0ed89e8c59e4 SHA-1: 7847d33203a67f1760f385a6acbd25ad2dc54918 SHA-256: fdb2c3e6eae09b50c4e4d566486f019ac42e9bacf0602d6536ab5d6a32b735d4
258 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages multiple critical vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) related to the Collab.getIcon, Collab.collectEmailInfo, and util.printf functions. The extracted JavaScript, identified as legacy_pdfkit_stage_000.js, is heavily obfuscated but detected by ClamAV as Js.Exploit.Shellcode-18. This indicates the script is designed to download and execute a secondary malicious payload.

Heuristics 7

  • 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 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.
  • 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_obj0008_000.js
e729c947975d0ddf81bf639a4bd4198cc2ec721a2852220488a68cbc542fc2ed
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2462 bytes
legacy_pdfkit_stage_000.js
a0fd2926642261c66decbcc680dd0e9c002562b628b08c6485d8dc29176f5673
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xBB9 8430 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).