Malicious PDF — malware analysis report

Static analysis result for SHA-256 a53683614720a0e5…

MALICIOUS

PDF

88.3 KB Created: 2021-07-05 21:37:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: aa101797726b8bd011db6d00868b759d SHA-1: 13d9a98e22cf92ec9302704b740a96de12dc7c1e SHA-256: a53683614720a0e57f4720d64b3ccca2cdaf759cd4fe5953a273fd707bd300c2
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to WordPress sites utilizing the 'super-forms' plugin, suggesting a link farm designed to distribute malicious content. ClamAV and ML classifiers identified this PDF as malicious, specifically as a phishing trojan. The presence of multiple distinct hosts and a high number of links per host indicates a coordinated effort to host and distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/k9e86bflhgc72hrde4oaj4fmhk/20486817746.pdf In PDF document text
    • https://www.brightfieldbusinesshub.co.uk/wp-content/plugins/super-forms/uploads/php/files/bemqo9i32u005ei1id2jaknest/66902694912.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/cbbaaf87cafe478f811283855235b840/13220376670.pdfIn PDF document text
    • https://kogan-photo.ru/wp-content/plugins/super-forms/uploads/php/files/e40a1b2607a655b2f7d6be22b370f504/lewozezifi.pdfIn PDF document text
    • http://zaintik.org/files/galeria/files/tavezagoxowo.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/zewuwexozozojebafu.pdfIn PDF document text
    • https://q-web.ro/wp-content/plugins/super-forms/uploads/php/files/88reu04tqhertnp6pf9lgskhu1/33602959029.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096536edbb82---venuxutivuluzagun.pdfIn PDF document text
    • http://webhenevents.com/clients/868374/File/13669229840.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077f909e78de---vasavelerevok.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/kafajagam.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/8d6ee94e4e9775065e5a2d6727520a00/jobebe.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/dagesepirilisajuf.pdfIn PDF document text
    • http://dlzj.net/upload/files/20210628013519930871.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8dad0bf49---volebiribivilufurepivev.pdfIn PDF document text
    • http://saharun.org/uploads/ckfinder/userfiles/files/44582978036.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/160a2f0529789f---44566642834.pdfIn PDF document text
    • http://satbietthu.com/luutru/files/46917044106.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/4g1jbkkurd970ukkv47miou4s6/mapozagozuwi.pdfIn PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/0a5e8220238b3c57db27433aa02f9bfa/jigerotejazapuwifevip.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8514d7d299---wugunudokutik.pdfIn PDF document text
    • https://badoza.net/userfiles/file/wigupavakikujubega.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/a9cc70d5aaae20519163a6e2d023881c/mopazenavifemopebo.pdfIn PDF document text
    • http://hacoauto.vn/upload/files/zatojutus.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6a01599144---donodegakodepagexizuvu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=hoarding+meaning+in+economics+tagalogPDF link annotation
    • 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_off0000f570.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF570 17636 bytes
SHA-256: f257cdc8f89f830bad92c091425c67bf8ee6d0fa171c3062417338c968fa0c18
font_01_sfnt_off0001239a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1239A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013bb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BB1 10704 bytes
SHA-256: c4760f82b132294585b911a15dccd0e891f7397b2e5d455d76a7db44c4dac655