Malicious PDF — malware analysis report

Static analysis result for SHA-256 8790ebae0b8e997b…

MALICIOUS

PDF

14.2 KB
MD5: 7021aa89f597c90b94f0998d3be393fc SHA-1: 6101b0eb24c8d9e278ba5af7a5dc20cf7dc75afe SHA-256: 8790ebae0b8e997bd6efd13f8e8e04e2423d295d90e6f521299f8f41db67d939
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF utilizes XFA form elements and embedded JavaScript to execute shellcode. This shellcode contains a URL, http://6.mamaswish.biz/string/defined_regulations-frequently.php?qcrrlgc=32:1f:1n:33:32&jpqm=1h:1l:1k:2v:32:2w:32:30:1f:1o&enmaj=1i&jrhba=tonpow&ofxmtmcf=kax, which is likely used to download and execute a secondary payload. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36962 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36962
  • XFA title base-26 eval stager high PDF_XFA_TITLE_BASE26_EVAL_STAGER
    PDF XFA initialize script reads an encoded payload from the document title, builds event.target.eval and String.fromCharCode from string fragments, decodes base-26 character pairs, and evals the recovered stage. This is an exploit-kit staging pattern; the static bytes do not prove a specific CVE by themselves.
  • PDF exploit shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF exploit shellcode contains a hardcoded http(s) URL — stored as little-endian %uXXXX Unicode escapes, or hex-encoded in a document metadata field (/CreationDate, /Title) and referenced from the decoded script. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://6.mamaswish.biz/string/defined_regulations-frequently.php?qcrrlgc=32:1f:1n:33:32&jpqm=1h:1l:1k:2v:32:2w:32:30:1f:1o&enmaj=1i&jrhba=tonpow&ofxmtmcf=kax
    • http://www.xfa.org/schema/xfa-locale-set/2.1/
    • http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/1.0/
    • http://www.xfa.org/schema/xfa-template/2.2/
    • http://www.xfa.org/schema/xfa-data/1.0/

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0041.bin
c06dcd026a7ea0536b63e07ce688691b585339a3ab7ff59065e546b56308c7bb		 pdf-embedded-file PDF EmbeddedFile object 41 at offset 0x2ADA 85 bytes
embedded_file_obj0042.bin
dda0835df994b8be920f715db36452f6cee7bb42bbc9c897f878a7b298ba8e91		 pdf-embedded-file PDF EmbeddedFile object 42 at offset 0x2B8C 1029 bytes
embedded_file_obj0043.bin
d7f7bd6434fff4670f50233bfe5cf596fac9d4d44d97771942e495ed6801d5e8		 pdf-embedded-file PDF EmbeddedFile object 43 at offset 0x2DA5 1949 bytes
embedded_file_obj0044.bin
3dd68f00f4fcb366a2a3a17c65cb2626eeddf5ea5713302d374310561d810169		 pdf-embedded-file PDF EmbeddedFile object 44 at offset 0x322C 144 bytes
embedded_file_obj0045.bin
10c03f88a5f0a0833dc5b2c8ac295b3a3c6f65e23889eb8cc1dc6fe29bf7f275		 pdf-embedded-file PDF EmbeddedFile object 45 at offset 0x32D8 77 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.