Malicious PDF — malware analysis report

Static analysis result for SHA-256 4351303160a1d205…

MALICIOUS

PDF

11.7 KB
MD5: 7a364bb9b8fb8a03e68c3ffafd328fb7 SHA-1: bbc90049ccd3452cda3017a6ae1062254caad683 SHA-256: 4351303160a1d205c3f34330617fb7298d181130345f3db68c4ccea2c0d6c662
126 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, specifically identified as a stager for CVE-2007-5659. The critical heuristic 'CVE_2007_5659: Collab.collectEmailInfo' indicates the exploitation of this vulnerability. The embedded JavaScript, recovered as 'annotation_subject_callee_hex_stage_000.js', is likely responsible for downloading and executing a second-stage payload. The presence of multiple JavaScript-related heuristics and the specific exploit identified strongly suggest malicious intent.

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
49b9bec9e49fbf50078bb638c05129939879119fcd3212039e581b762fa951ec
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5133 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).