Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb57830dc0a49428…

MALICIOUS

PDF

81.7 KB Created: 2021-06-26 15:07:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 974b814262c27cb796acee9956ef3a8b SHA-1: 1f0ee9ac20ac4c1e3c603794d1204dfadf7d43a2 SHA-256: cb57830dc0a4942810d406db9f59622065799502f8a3fcbd84ee0a5c5bf6704b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://infrive.ru/uplcv?utm_term=the+babysitters+club+kristy%27s+great+idea+pdf PDF link annotation
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/jh5vi148i0is9min3r1rah8ag7/paliwakigoj.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/db1e1f102ab31d6ea30911bd6ddbeca2/97067030565.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a3c1e3b9c6---kekevibanukozaxuj.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/bupajuferoxuwi.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b55c7bbb60d---sopoja.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/fbm3a1p3huf7qgtfus3mfhehd0/punitilizavedolizijak.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a994da3ca30---vanavasin.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/zopirejovib.pdfIn PDF document text
    • http://willismctyeire.com/clients/c/cd/cd1fd5262213d36872a77bd42df049b7/File/95791091201.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/f163a358f15f2d93abbdaa21601bc300/wegugolenogifilivuwawaj.pdfIn PDF document text
    • https://www.prestigeautobody.com.au/wp-content/plugins/super-forms/uploads/php/files/318cb2802135165f7c73dcb66aaffc6f/6345271636.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/6a99f01a25b47cfa143a238c4fc0d974/44739976119.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/72654594483.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/uivth4fgc005sbkpbae8cun3db/pomuxejorofa.pdfIn PDF document text
    • https://amadesafar.ir/basefile/amadesafarir/files/zasigaloliridonupixonaja.pdfIn PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/5bee0fb30b9552deb1ec01072e2e0613/14816685086.pdfIn PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/44191175325.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16098c0ab12b27---6812317505.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3148b967a0---nevojibaxe.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16083a354b7824---95773032636.pdfIn PDF document text
    • http://domholidays.com/userfiles/file/15626823512.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/a3f975ccbb031d98e0144ca496dc0382/gerawusi.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/6358127820.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021061615545940.pdfIn PDF document text
    • http://qiangka.com/ckfinder/userfiles/files/popematutotezivubek.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160802281e13a9---jakirusasijonavurefenewi.pdfIn PDF document text
    • 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_off0000d78b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD78B 11116 bytes
SHA-256: 4109f436eafb7c64d60fc80e2265ba19304194c9e50a9bdb5e2614d9933386d1
font_01_sfnt_off0000f14c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF14C 17608 bytes
SHA-256: dc239398e5bf8f486c9e62880f1dae8e2c64af4921303e35e9151f4561cf70b4
font_02_sfnt_off00011ef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1