Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b328f29c46ec21d…

MALICIOUS

PDF

94.6 KB Created: 2021-09-04 00:58:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4f77c16de11b55398b6f94e0b3761920 SHA-1: c1e475b39220dd35e475a9073ace46e06ea76c08 SHA-256: 9b328f29c46ec21da9c2219dc5cd6f2cac5420781374e1c5941966d66e078646
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised CMS uploads. The primary purpose seems to be directing users to external content, potentially for phishing or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://coretry.ru/uplcv?utm_term=100+common+words+in+english+pdf PDF link annotation
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/93e545013cd2468cddcf27f3c227ce71/60630470053.pdfIn PDF document text
    • https://boumqueur-edition.com/upload/fckeditor/file/xomabig.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021071802340223.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/62a1b151cb9a0347dfaed86df635c7a7/gakipegorevofubitukigiwuf.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/f840fdb445b6b8e41efbbf3d5099dfc1/76774816961.pdfIn PDF document text
    • https://groupburuemas2.com/contents//files/delopijijamozagebexalevug.pdfIn PDF document text
    • https://asi-filter.pl/files/file/fivarisutujurifimuw.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/lnt8qbj7lvvdfak7avi8u304m0/xenebarinozufiwineforezun.pdfIn PDF document text
    • http://acrclubinversores.com/files/galeria/files/ronozukaxin.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/refezusapoxojopixosotig.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/wagimigewo.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160de8c08f10f0---27067819992.pdfIn PDF document text
    • http://hzeiger.com/userfiles/file/95101176100.pdfIn PDF document text
    • https://agmatbaa.com/upload/files/dabopanumamerezuburokuwep.pdfIn PDF document text
    • http://caratow.nl/userfiles/file/80731815160.pdfIn PDF document text
    • http://selfmadefilms.nl/userfiles/files/sotat.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210828065053.pdfIn PDF document text
    • http://misspacificus.com/clients/873634/File/lupipakogepeli.pdfIn PDF document text
    • http://lawngo.net/fckfiles/rufifakafixo.pdfIn PDF document text
    • http://archimax.ch/dynamic-images/cms/file/75835345826.pdfIn PDF document text
    • http://abcbyspu.net/ckfinder/images_store/files/54805446425.pdfIn PDF document text
    • https://avflash.nl/upload/files/lifitupagubib.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_off00010b2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001233c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1233C 18952 bytes
SHA-256: e35a0ba1030041a0ef01d1311b9e70d53d13d4f8de9a84dbb5616000b5f5a85f
font_02_sfnt_off000153d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153D1 10968 bytes
SHA-256: 9af799533612c68484ff9187212f1ec55691229425e26c61241c1975df1b967e