Malicious PDF — malware analysis report

Static analysis result for SHA-256 13aef03069f23ef1…

MALICIOUS

PDF

83.3 KB Created: 2021-09-16 21:19:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 83284aaa91cffce454b77595c42728b6 SHA-1: cc7e0eeba80a23c2c86caf416a1f520fed90843d SHA-256: 13aef03069f23ef18536bb8d3500a5c17a4237ac3d94c4304d548d205cee6612
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or use disposable hosting, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple external links suggests an attempt to lure users to potentially harmful sites. No scripts were extracted, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • 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://philabc.ru/uplcv?utm_term=prokaryotes+differ+from+eukaryotes PDF link annotation
    • https://m-astar.com/UserFiles/files/kopadepizabutesokab.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/budegosul.pdfIn PDF document text
    • https://somogyplusz.hu/files/gigametesosofapikemu.pdfIn PDF document text
    • https://derya.afmiletisimajansi.info/resimler/files/31201673516.pdfIn PDF document text
    • http://spy-military-labs.com/userfiles/file/fokukejobudotomokumi.pdfIn PDF document text
    • https://pharma-tools.pl/galeria/file/65285445514.pdfIn PDF document text
    • http://atlonnuri.org/UpLoadImage/editer/files/84007605126.pdfIn PDF document text
    • http://hizirferforje.com/admin/fckeditor/editor/images/file/gowufipulovozegunuxu.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1613f47eb644af---2272654690.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16130288e32e10---mukevokan.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130959f7a6b9---93255428186.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/53469011fed889b31b07a32db8737e73/dolagizetejurufuka.pdfIn PDF document text
    • http://massvt.sk/editor_uploads/system/files/tesofaxanikaladix.pdfIn PDF document text
    • https://ltes.tw-goods.com/UserFiles/files/vukar.pdfIn PDF document text
    • http://mientrungland.net/uploads/image/files/lufopugijagibilurafeku.pdfIn PDF document text
    • https://rwd1.thadv.com/upload/files/97002031951.pdfIn PDF document text
    • http://xhzhengli.com/upload/48430009735.pdfIn PDF document text
    • http://sibzakon.ru/ckfinder/userfiles/files/rifularefevifezefawe.pdfIn PDF document text
    • http://st-johnson.com/Uploadfiles/files/tolojunobu.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/0cfm1859elrqhog11abi43peh1/nazavipon.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7025ec77f---xutegubapuko.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d7cdb44cb1---nomupuxegegesojene.pdfIn PDF document text
    • https://pbpkrosno.com/fckfile/judofefibibuz.pdfIn PDF document text
    • http://gruaszarate.com/ckfinder/userfiles/files/wufatutobanewoboso.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_off0000e14b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE14B 18000 bytes
SHA-256: 42df5abf589396f93f509a050b501a4064a210b511c4a58b13a7f19e34d9c522
font_01_sfnt_off00010ef6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001270d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1270D 10672 bytes
SHA-256: 627d7ebce558327ea7141dcc38b8fe03f98433c8cf22e4b043c463af36cc138b