Malicious PDF — malware analysis report

Static analysis result for SHA-256 f83a1e0340f83579…

MALICIOUS

PDF

88.0 KB Created: 2021-09-17 06:43:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1ba8db0fe47dbf89de14f4a5c9eabcd8 SHA-1: 4abfc8ed9391df2d39c0c58d234a86f2cdf7ef45 SHA-256: f83a1e0340f835797ee8bcac478c92e65bae5475aa733a850aff463f988801a0
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to various websites, including those hosted on compromised WordPress installations. The presence of multiple links and the nature of the hosting suggest an attempt to distribute malicious content or phish users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://ktcz.eu/files/files/70124705223.pdf In PDF document text
    • http://interstyle.org/content/xuploadimages/file/palonederugidatosaboluli.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/27378124919.pdfIn PDF document text
    • https://jurad.eu/files/file/balomidazemux.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b9c484ff03---24832677113.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16140941642bd1---xaxovedotemumofoxivaj.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/13e5ebbfe7b1261193d27092a2697ad7/kepoxamipepabeb.pdfIn PDF document text
    • http://ekmeta.lt/failai/file/vunubarof.pdfIn PDF document text
    • http://lhdrum.com/User_File/UpFile/file/20210902024326_OTg3MDA5ODA4MzQ=.pdfIn PDF document text
    • http://giasudaihocsupham.com/Images_upload/files/27052030543.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/vexaregoni.pdfIn PDF document text
    • http://personal.sut.ac.th/chantira/port/ckfinder/userfiles/files/wovuvurofesoronazap.pdfIn PDF document text
    • https://kalendarz.probik.pl/fckeditor/userfiles/file/78066395366.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/2af8cb8a38504855237598dc807c7cfb/4399887773.pdfIn PDF document text
    • http://wangguanhardware.com/userfiles/file/99089769916.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5511be5e0---35470929494.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///gunawasegoginadafozibu.pdfIn PDF document text
    • http://xn--80aaffebba2apgigwiiececnggk9e4k.xn--p1ai/pict/file/79915350156.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/2t5spfsd1d6i46abo006josdqe/gosilalolijifevotugaxum.pdfIn PDF document text
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/98441074059.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/sigalatufa.pdfIn PDF document text
    • http://progfin.pl/userfiles/file/rurijifuwumafesabav.pdfIn PDF document text
    • https://anjingliar2.com/contents/files/jigijufazefexo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=best+android+corporate+email+appPDF 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_off0000f37d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF37D 10728 bytes
SHA-256: f83a5b5f5be62b1bdc060bf01e3188c2d31e6bca441527fb94412733555ffa84
font_01_sfnt_off00010c1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C1E 17812 bytes
SHA-256: 1c7dbd658d1402b4c5a161471f008f4d24c02abb2d9cf485389ae80056e9a846
font_02_sfnt_off00013a8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1