Malicious PDF — malware analysis report

Static analysis result for SHA-256 528434991b10d49a…

MALICIOUS

PDF

11.7 KB
MD5: d56a35ec5f86e507ac619e48ab3e55ab SHA-1: fa4a9c7d99313f318fb4d6bdeb0566f4c3419703 SHA-256: 528434991b10d49aee095f310c4685b93b368885f2e4754aa68d2c9629b2147f
186 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is triggered by the CVE-2007-5659 vulnerability, specifically using the Collab.collectEmailInfo method. This JavaScript acts as a stager, deobfuscating and executing further malicious code. The ClamAV detection 'Pdf.Exploit.Agent-36063' confirms the malicious nature of the file. The primary attack vector involves exploiting a PDF reader vulnerability to download and execute a secondary payload.

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
2f078d82565e1ddceb7de28f263831d9a1f4354980932727e249916c41641c2f
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5032 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
ef150126a3f68282461329358e77c88e7081aa0bc3f820d7040a8d31a2df4441
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12012 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
cdcf707800d8f95bb4ca819e1b40c4ad8e74d543e0a9f99fc145a0669f3cc814
deobfuscated-js PDF JavaScript deobfuscation pass 66835 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).