Malicious PDF — malware analysis report

Static analysis result for SHA-256 efb56e279b026300…

MALICIOUS

PDF

11.6 KB
MD5: 742ce8ad264844c94cbb35a668e7d23a SHA-1: f8e4ccd7ace79a82bd57139dfb516647f078b674 SHA-256: efb56e279b026300052c31b889780781d5dfe40f384f2136bf135584ef6698b4
178 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is obfuscated and designed to act as a stager. The critical heuristic 'CVE_2007_5659' indicates the exploitation of a known vulnerability (Collab.collectEmailInfo) to execute this JavaScript. The JavaScript is recovered and deobfuscated, revealing its role in downloading and executing a second-stage payload. The ClamAV detection further confirms its malicious nature.

Heuristics 6

  • 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)
  • ClamAV: Pdf.Exploit.Agent-36180 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36180
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • 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_obj0007_000.js
17e11d5c0e7abf0d400044cf4333a75f193b35e2745d65fea155eb4de3ce3aa6
pdf-javascript-stream PDF /JS object 7 at offset 0x1A6 628 bytes
annotation_subject_callee_hex_stage_000.js
d41764216ae7e708095f0bf4f820bc13eab31c1be6279cc271eb41a02645321b
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14F 5101 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).