Malicious PDF — malware analysis report

Static analysis result for SHA-256 96cb488a3e660254…

MALICIOUS

PDF

11.1 KB
MD5: 18e875828fed935964453d42901651f0 SHA-1: b57a40a84350e2ee47deade46a2a864ea92a9f3f SHA-256: 96cb488a3e66025409ec6d8e58941c11264335b5ac6b05445482d37a6d825b34
126 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, specifically identified as a CVE-2007-5659 exploit targeting the 'collab.collectEmailInfo' function. This JavaScript is heavily obfuscated but is recovered and decoded by the analysis engine. The primary function of this script is to act as a stager, downloading and executing a second-stage payload. The presence of the 'annotation_subject_callee_hex_stage_000.js' file further indicates the malicious nature of the script.

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)
  • 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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
c860bd3a1b8438b37e98a599719a1868ae540624631f091272ffef48912644f4
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 579 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
annotation_subject_callee_hex_stage_000.js
ffbb3c4eb3f855877e216da9c16e00efcc46d546be5477bc54e7b0960acf3bd0
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5138 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).