Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9d9b238beb4d591…

MALICIOUS

PDF

12.1 KB
MD5: cd03f1ee73066d9364652c9d3ebfcd95 SHA-1: dfd68dd71cf5d9b002be39956fd2da15467efb89 SHA-256: b9d9b238beb4d591e5e71044b94d00114f6199527c9ad5c6617122cf4d9ff8f7
186 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, specifically leveraging the CVE-2007-5659 vulnerability through the Collab.collectEmailInfo function. This JavaScript is heavily obfuscated but appears to be a stager designed to download and execute additional malicious content. The presence of multiple deobfuscated JavaScript files indicates a complex execution chain. The primary attack vector is the exploitation of a PDF reader vulnerability to run arbitrary code.

Heuristics 7

  • 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-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • 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.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
2744161e1da3a769813deb9f4926a131169a351f516c506af7a55c7d80bef3f6
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5141 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
f6f4f330526b8d82a2e1663427fe7fd08f7e13acbfd375532fcc43163ee86b03
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12185 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
7873e9983950436e418b70c5630bad0ed0c8c0862b204a133ab8a318ed08044b
deobfuscated-js PDF JavaScript deobfuscation pass 77984 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).