Malicious PDF — malware analysis report

Static analysis result for SHA-256 8732766b40554f74…

MALICIOUS

PDF

83.9 KB Created: 2021-09-09 23:21:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1cf738b5c50e4e5e9ded1a375c116d27 SHA-1: 06620380fd1a458bea375188b1804ae527d3e965 SHA-256: 8732766b40554f7460a11623e6a380af4c55458e797316f6c35a906b25f74ebe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. 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 0.9981

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://synerhu.ru/uplcv?utm_term=huge+digital+clock+apk PDF link annotation
    • https://abcelectricalonlineshop.brilliantwebtech.com/userfiles/files/wedemolazerawa.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/ieta2jf6dliunaj1lnmuj9vuig/26889039201.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138c40aada26---90320083587.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/57385619316.pdfIn PDF document text
    • http://sunmoon-glory.com/web/upload/files/8618742812.pdfIn PDF document text
    • http://studiosantese.eu/userfiles/files/18725807763.pdfIn PDF document text
    • http://yds-wcv.jp/free_images/files/molikufise.pdfIn PDF document text
    • http://btsoft.vn/uploads/files/29396845770.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/6755bd4583aff8027371f046f0ce517f/talafomoripefomosexe.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/2e51fa70213484a85f91ad320f700701/verujekopovorofukipogovax.pdfIn PDF document text
    • http://studiocommercialedelpiano.it/userfiles/files/gisukedewagazixunet.pdfIn PDF document text
    • http://fkm-lux.by/var/upload/file/43632642513.pdfIn PDF document text
    • https://www.funes.gob.ar/ckfinder/userfiles/files/23877660558.pdfIn PDF document text
    • http://administratieindex.nl/images/uploads/bakezib.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/20860009377.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/zenajupazakopewufus.pdfIn PDF document text
    • http://africareview.in/userfiles/file/ridinezomoniloduxusulom.pdfIn PDF document text
    • https://gastriklandsbf.se/UserFiles/files/33404495537.pdfIn PDF document text
    • http://tw-tms.com/uploadpic/xw/files/50104561768.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16136d6ec3a5a6---35011595538.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138373918ad9---6314032682.pdfIn PDF document text
    • http://sromedical.com/file_media/file_image/file/34449584433.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_off0000e361.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE361 18196 bytes
SHA-256: e2d910ee50a2ca954abd36c9a5abf2f3a0ab5a9a0dfa06aec6054cc57c070b4b
font_01_sfnt_off00011237.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11237 10500 bytes
SHA-256: f0fa740dfdf44e6b9fbff145162143946cd6ac6e86dd90d473280050244b3604
font_02_sfnt_off000129f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1