Malicious PDF — malware analysis report

Static analysis result for SHA-256 98545a5a6a2e8c85…

MALICIOUS

PDF

71.5 KB Created: 2021-09-06 20:53:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e4b9d42fe9a59c72a15910d711db05f4 SHA-1: 9d67e30eb6e1072c665ec87fdba89a1e2d907a59 SHA-256: 98545a5a6a2e8c85c6ed34c98deeb7fdc4bee02a74e9e6e8a48cdc76bd269ba1
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. The primary purpose appears to be directing users to potentially malicious or phishing websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9959

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://synerhu.ru/uplcv?utm_term=peronismo+resumen+pdf PDF link annotation
    • http://bearings-home.com/userfiles/file/jolodaviba.pdfIn PDF document text
    • http://webhenevents.com/clients/868374/File/96780307626.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/1f29c6d0b166430f4138d878e4035a8e/padedotogowodisizosize.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/baf69fe6fbb0a37a200a7b19f6f1cff6/duzapozenu.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1552e191cd---wowes.pdfIn PDF document text
    • http://prefinancovaniehypoteky.sk/res/file/88046147499.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/12b7233e049055f063b16c038db79487/29169919345.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/cbe6312c39000da6a9541e5af7df7c40/53979644455.pdfIn PDF document text
    • http://varadimasszazs.hu/uploads/files/21109850453.pdfIn PDF document text
    • https://fiscalonline.ro/app/webroot/files/userfiles/files/79725802911.pdfIn PDF document text
    • https://alyosserspneed.com/userfiles/files/kezujobibukurewirizijege.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/334c4491692be1daa096a484417649e6/subotenexekugopa.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fcdad08101b---10515312594.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/vikuboweki.pdfIn PDF document text
    • https://www.perfumista.co.uk/wp-content/plugins/super-forms/uploads/php/files/17cf7fa156391349f7f0d80c334e9602/36284576944.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/2fns0k2canb66rq81braliddgi/79767715656.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/90110481633.pdfIn PDF document text
    • http://industrialsupplies.pk/userfiles/files/47633693870.pdfIn PDF document text
    • https://eqonetech.com/upload/userfiles/files/xegukufaguduzekefoga.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/a2126c8d737e7047cc6e3c9a5d5290de/binigizoroxaboloxe.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16075f2a9ce57f---81351389316.pdfIn PDF document text
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/a32f1edcac1f00378126fb210439275f/xewazixajekipi.pdfIn PDF document text
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/5c81e00f782771545b9255162f2f3d51/42010436822.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_off0000b646.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB646 10456 bytes
SHA-256: 3f9d100127e01561b80b986208654e19089b3f4901cfa40b19a385da6d61a975
font_01_sfnt_off0000cdf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e602.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE602 16748 bytes
SHA-256: 612e275d9297184e4a76aa3c004ffec9ca0d79ba207189c6fbd064d8ee05815c