Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d803727abe1a5cf…

MALICIOUS

PDF

43.9 KB
MD5: 9b7500056f68862ef6bb18cdf88761a0 SHA-1: 16329efae084932adebd0b229c53f3dad86b5bbc SHA-256: 3d803727abe1a5cf23ccb9631734c658a790bacfe9d14f5bc638738ff172ae11
194 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, and PDF_EVAL. The presence of PDF_U3D_CVE_RELATED suggests exploitation of a vulnerability related to 3D content parsing in Adobe Reader. The ML classifier strongly flags this PDF as malicious. The embedded JavaScript is heavily obfuscated, making its exact function difficult to determine, but the combination of techniques points to a likely exploit delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • U3D/3D content in PDF — Adobe Reader 3D parser CVE-family indicator high CVE related PDF_U3D_CVE_RELATED
    PDF contains U3D (Universal 3D) or 3D annotation content — CVE-2011-2462 and CVE-2009-3953 are critical vulnerabilities in Adobe Reader's U3D processing that allow arbitrary code execution. U3D content in PDFs is extremely rare in normal documents.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • Suspicious extracted artifact medium 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.
  • 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)

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
93f3fdceb942579280d3f196f445d15453064a5ad968d92ae645d590c8b83fa8
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 166 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
0b20966285e12a83cb75c6c85ec527b927803b743faf2af7383e9fdf4363e588
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x29F 22791 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
414705c26262d792de2720254ea0260f1bac4980cdc7fe224c37c41a09acf468
deobfuscated-js PDF JavaScript deobfuscation pass 228798 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s). Carved artifact contains 1 long hex-escaped blob(s).
u3d_00_off0000435a.bin
70cf2aead4823e6d2651c9281eed0aa967449da358f439efb9e8e707421175e0
pdf-3d-stream PDF U3D 3D stream at offset 0x435A 28021 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.79, consistent with packed or encrypted content.