Malicious PDF — malware analysis report

Static analysis result for SHA-256 84d4e5cd51b77e4d…

MALICIOUS

PDF

12.1 KB
MD5: 3a2587cf298d654dbbc4e5b0ba88da45 SHA-1: 018f21ae110e7efcb01db3535b1e55dd74a9c8be SHA-256: 84d4e5cd51b77e4d4b020c5e87a65cf1e3ab6b0b67d828c5dc59127c6a08725f
290 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains JavaScript that exploits CVE-2007-5659 in Adobe Reader. This script is designed to download and execute a second-stage payload from the URL http://riarqejrncz.com/nte/GOLDMN.exe/yH4fba712cV0100f060000Rde9e11c8102Te32d8d88J00000203200. The presence of shellcode and a download URL strongly indicates a malicious intent to compromise the user's system.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 9

  • 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)
  • Adobe Reader APSB08-13 patch-range version gate (CVE-2007-5659) high CVE likely PDF_JS_ADOBE_APSB08_13_PATCH_GATE
    PDF JavaScript gates the exploit payload on (>= 8 && < 8.1.1) OR (< 7.1) — the Reader 7.0.x / 8.0–8.1.1 window patched by Adobe APSB08-13 for the CVE-2007-5659 Collab.collectEmailInfo buffer overflow. Only kits that target that exact bug check both of those patch points; benign scripts do not.
  • ClamAV: Pdf.Exploit.Agent-36179 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36179
  • 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.
  • PDF JavaScript shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF JavaScript shellcode contains a hardcoded http(s) URL stored as little-endian %uXXXX Unicode escapes. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://riarqejrncz.com/nte/GOLDMN.exe/yH4fba712cV0100f060000Rde9e11c8102Te32d8d88J00000203200

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
e89d7054d228dd0d7d4de9a02d1607a443ba297f326673115b5825c1b6cb184a
pdf-javascript-stream PDF /JS object 7 at offset 0x1A6 823 bytes
annotation_subject_callee_hex_stage_000.js
e16a629403a2b41c73b8c99ff3b632f951398c4dbc2d0a05b7e61876d819ec6d
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14F 5269 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).