Malicious PDF — malware analysis report

Static analysis result for SHA-256 2573724bf8817e7a…

MALICIOUS

PDF

69.9 KB
MD5: f5b69c12c5e3954efae9148ac5c24d4e SHA-1: f320fc4f64b806a31c7d931588a36635207ef66c SHA-256: 2573724bf8817e7a431cb1a0ef09778304586e9be25a6e720697f4e32fc33e06
258 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages multiple known vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) through the Collab.getIcon, Collab.collectEmailInfo, and util.printf functions. The extracted JavaScript, identified as legacy_pdfkit_stage_000.js, is obfuscated and 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
d3807db5055ac61736e76a6d5ecb4d9d1dccaf43d490566725cd5b0039568934
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2089 bytes
legacy_pdfkit_stage_000.js
2e7bd32e72c324e63b87ea551f664f537af1e257b29b0987d7602aa718606000
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xA44 4578 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).