Malicious PDF — malware analysis report

Static analysis result for SHA-256 830fa645d9cd1de5…

MALICIOUS

PDF

12.1 KB
MD5: c7888eb8ecd1b29e12c936b81ad08e9c SHA-1: 1f0e8cc7bbf7c1eab2bfac655a3f328f256ffe10 SHA-256: 830fa645d9cd1de59c2a603703593fbda6e2084e18a72affd62d7577891041bb
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF document contains embedded JavaScript that is obfuscated and staged. Heuristics indicate the use of CVE-2007-5659, specifically the 'Collab.collectEmailInfo' method, to execute this JavaScript. The JavaScript is decoded and then likely executes a second-stage payload. The presence of multiple deobfuscated JavaScript files suggests a complex multi-stage attack. The exact nature of the final payload is not determined from static analysis alone.

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
dadc72347dad58f787b67c6e198c5926a21960ea27426c263acdee6d5da631aa
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5152 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
30e50155e719fce48eaf93d618ecd627370bd1d2b9f03b28a9b774256edffb44
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12279 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
080dff4b57baf6d4dfa7b9ade45342b5317f31061ac3a15679e438fbbb5b9d55
deobfuscated-js PDF JavaScript deobfuscation pass 73989 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).