Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc8d92aa0be9b0c4…

MALICIOUS

PDF

82.2 KB Created: 2021-09-04 09:29:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: e621680bbba0a942c43d34eb9fdda398 SHA-1: c82ad73f8267523a8f4e75b5301da5e5d093414a SHA-256: dc8d92aa0be9b0c4b4ac01b3ff0c06e3ae56660de006078964e04e086979b69f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating link farms on disposable hosting, suggesting an attempt to manipulate search engine results or redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://smidgel.ru/uplcv?utm_term=20+figures+of+speech+quiz+pdf PDF link annotation
    • https://ymy-tea.tw/upload/files/tugodubuwex.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/467381c2fafc491c50ce67319c8de54e/39446102342.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e67f85d3a30---2673430491.pdfIn PDF document text
    • http://diodelumi.com/ckfinder/userfiles/files/14734815954.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160baebe6e8e54---19261019086.pdfIn PDF document text
    • https://mnlex.it/file/45021176881.pdfIn PDF document text
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160aa907f37d76---86771448500.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/552d71a47699415fa319f9141865e738/53353925928.pdfIn PDF document text
    • http://cosyromania.com/media/file/89695579577.pdfIn PDF document text
    • https://leo-translate.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16087b07457fcd---62657262631.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/dutenesojoxujagukoram.pdfIn PDF document text
    • http://thecoferfamily.com/clients/7/78/7892d776c92a08c80f86ebc6236678d2/File/84721125590.pdfIn PDF document text
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160721fc699069---15130815256.pdfIn PDF document text
    • https://castel.ro/userfiles/file/67863466191.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/52324115436.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/71bdb888dc2fbe4571511d9425e86898/risizazajeriwedemedisi.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/vvjb014bmg17vjsd5kneqehbl4/40110789222.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f3d154702aa---wazidiv.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/726792e1e7418272b371a06922f8377e/damuzosuzadule.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/44876458418.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a74c5836fe3---868966057.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/19791e2b408639171ea45594062af333/59339554594.pdfIn PDF document text
    • https://megatekspb.ru/sites/default/files/uploads/gofesopamijudokozebosom.pdfIn PDF document text
    • http://phannhan.vn/files/usersfiles/files/zidonukoroluluzi.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/0792b44661ab6a094383eb790c3c1a2e/20764650178.pdfIn PDF document text
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/9f8c88d531cb367f330a528f6229a065/dixazajepetiperibumujinos.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_off0000db26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB26 10940 bytes
SHA-256: 078b76054bdd7a2015cf2171f64f1fbc0cdc0fd847183d2b55a7552706514393
font_01_sfnt_off0000f41f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF41F 18496 bytes
SHA-256: 3833bf58a3018390650d493d064d06140ebe27f6f52b9ae0fed71ef4c5772253
font_02_sfnt_off00012336.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12336 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1