Malicious PDF — malware analysis report

Static analysis result for SHA-256 0ca35f4d0c55aa7e…

MALICIOUS

PDF

11.7 KB
MD5: adc3a48180c78878379cd5f2977ec44a SHA-1: 0c9145ad9f84054a8878f040661817cca3a9015f SHA-256: 0ca35f4d0c55aa7e5eb6e8b83c6bff6e7af81073687569ba3e68c6cb2bdb5530
230 Risk Score

Malware Insights

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

The sample is a PDF that leverages CVE-2007-5659 by exploiting a vulnerability in Adobe Reader's JavaScript engine. The embedded JavaScript, specifically the 'annotation_subject_callee_hex_stage_000.js' script, is designed to download and execute a second-stage payload from the URL 'http://aabalhtabvf.com/nte/prox.exe/yH74a7e8f6V0100f060006R108429ee102Tbb858c48203l000c'. This indicates a downloader or dropper functionality.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 8

  • 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.
  • 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://aabalhtabvf.com/nte/prox.exe/yH74a7e8f6V0100f060006R108429ee102Tbb858c48203l000c

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
83c89bafa116d9c91eff0b9ebda502f5bf0baa04c36fa774c6ebc2756ba3479f
pdf-javascript-stream PDF /JS object 7 at offset 0x1A6 585 bytes
annotation_subject_callee_hex_stage_000.js
a293b347416f6dd0a290b0b2e30beff0f1436ff9f3c7b561a9b68eefb05d6098
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14F 5163 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).