Malicious PDF — malware analysis report

Static analysis result for SHA-256 8436f4caa997bd68…

MALICIOUS

PDF

119.2 KB Created: 2021-09-05 18:55:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: ae14a583f282262dc39668f6bb8089ea SHA-1: b7cf520debac400d90a30926089558e173708373 SHA-256: 8436f4caa997bd68bef20d1b0c8ae0f03424a11ed36c953c64ef3bb7dc0f2359
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a password-protected-archive lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://infinijewelry.com/userfiles/file/17863504370.pdf In PDF document text
    • https://insinkerator.us/images/uploaded/file/pegaj.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/l33s3n7iib92ojm66fedajta33/13709524418.pdfIn PDF document text
    • http://podwierzba.eu/ckfinder/userfiles/files/15502371334.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/52eac7e298f09e88c1a33f7aa4983ded/wurafadukazomeguwalekufo.pdfIn PDF document text
    • http://smit-electronic.hr/upload/datoteke/13844963944.pdfIn PDF document text
    • http://sunnysidehigh65.com/clients/d/d0/d00d1ad1640c45b888f5e58ac216a5d1/File/davinegebixelabekiwi.pdfIn PDF document text
    • http://jjkxmy.com/upload/files/202106270003509176.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/39328269668.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608632f426ae4---sejimowenad.pdfIn PDF document text
    • https://cosmopolitanhotelbg.com/uploads/wysiwyg/files/65462640420.pdfIn PDF document text
    • https://capitaleny.com/wp-content/plugins/super-forms/uploads/php/files/4ded23c78825e07939db199822aacd8a/34310835145.pdfIn PDF document text
    • http://xaydunglenguyen.vn/upload/files/42128f.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160aa871e20584---63556038339.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/23672407209.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c4160274d---58806000229.pdfIn PDF document text
    • http://tangiahoang.com/skinkorea/Images_upload/files/37929687070.pdfIn PDF document text
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/560667e17ef209502ab92fdc09a28df3/57427911038.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/uqqecadr5i9mvfpengq0g8cjoe/larituvosabelawusex.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160afe14bdab45---volokalavuvixa.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c91a11b15b---gosunidifisobigu.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160887a1258cc5---24709806458.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d0be6ec6409---siwifovibisuzeruloso.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/48493946667.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa32ce530b---bosepuvujetage.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=rexroth+indradrive+c+user+manualPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00016e18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16E18 18228 bytes
SHA-256: 1ae53bd95abb7384fc4ead27bcbb27f232c616e9d5f1d23c08a3184cc273487d
font_01_sfnt_off00019d9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19D9B 10948 bytes
SHA-256: 5dc76a3e0c134af2e6ebf8219e4aee0cd165c9b541a638fbb02dda0c99e38cdc
font_02_sfnt_off0001b6e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B6E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1