Malicious PDF — malware analysis report

Static analysis result for SHA-256 36b05e27a56bb9f9…

MALICIOUS

PDF

12.0 KB
MD5: 016991878d9468f8e6fe8c759f19ca6c SHA-1: b305546fa1d06a3be3a0af6e0600fa1da99ccb2c SHA-256: 36b05e27a56bb9f91cfd1369f62b8d1109e27d67ad52c693ef6df4008ee050f1
216 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, triggered by the CVE-2007-5659 exploit targeting the Collab.collectEmailInfo function. Heuristics indicate this JavaScript acts as a stager, likely downloading and executing a second-stage payload. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as Pdf.Exploit.Agent-36063.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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
3193e07718173bc1085fbce0cca076aeddfc367f812f9b9aa04ca260860046f1
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5090 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
735fb4c52abb0ac47198c3482e290ead2b05ca3f03ec8f2b44a26e808cb1d9e8
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12052 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
2b72ff6435afee266a1e81e8383185a97fddff6d59b928da0682a8b80ea6c3a8
deobfuscated-js PDF JavaScript deobfuscation pass 72494 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).