Malicious PDF — malware analysis report

Static analysis result for SHA-256 40b094c22d275c56…

MALICIOUS

PDF

12.0 KB
MD5: bbb758ca51f24cf8907d9499605638ff SHA-1: 8aa8ec3a485593ce246ff03cddff8ec8418eacec SHA-256: 40b094c22d275c567818bef269d4d58284dadb766d460485b997b4ff74f139e7
216 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, triggered by the CVE-2007-5659 vulnerability using the 'collab.collectEmailInfo' method. This JavaScript is heavily obfuscated but is designed to stage and execute further malicious code. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving the download and execution of a second-stage payload.

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
049dac1474a60ea905415a818bc520ed2f82bf1b2120ed6ed763eb1ad244f1e7
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5166 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
9ffe157d76602ec32dcf859f7ea6634c57362acb1e394294582e98bf3bce9e5e
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12102 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
e4d9f6bfe9e29918bf1eac42ec214cb3fa14e16efe70b7155e2811c4fef85032
deobfuscated-js PDF JavaScript deobfuscation pass 73421 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).