Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec13c45375f96af3…

MALICIOUS

PDF

79.3 KB Created: 2021-09-06 14:02:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0b2fae4396a96976a49a80c884cb146e SHA-1: 719c00dd48ef2ae35fab9a113100a93bd29bdab9 SHA-256: ec13c45375f96af368edf76e6f895bd1648a85a5af181c29adc2af99f3c35201
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were directly extracted, the nature of the URLs and the 'link farm' heuristic point towards a phishing or malware distribution scheme, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://asokmontridental.com/userfiles/file/92599450847.pdf In PDF document text
    • http://driver-jazda.pl/upload/file/goxubefuj.pdfIn PDF document text
    • https://fier-forjat-valimet.ro/ckfinder/userfiles/files/kalonivosuwif.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/36373135602.pdfIn PDF document text
    • http://peusch.lu/userfiles/files/monafebivoxirugole.pdfIn PDF document text
    • https://aravlicraft.com/cmsCart//upload/file/33492526231.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd0a937456f---mapaluwasavawafapakafuga.pdfIn PDF document text
    • https://www.tvmreza.tv/ckfinder/userfiles/files/2852560214.pdfIn PDF document text
    • http://shesob.com/file/files/51075085316.pdfIn PDF document text
    • http://bayzones.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/sagoselav.pdfIn PDF document text
    • https://dienlanhbachkhoa.info/upload/files/34407175271.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16091acaf7cc2c---netikosapezolepiboxuwaner.pdfIn PDF document text
    • http://verdantnorwich.com/clients/3/30/306756bb587dffcd11ca74610d845a16/File/kovulaguwutajotag.pdfIn PDF document text
    • https://senarathgroup.lk/assets/media/file/66183506272.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/tosakiwazafare.pdfIn PDF document text
    • https://ipekyolumedya.com/resim_galeri/file/fuzinedidosazadusad.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/fulidepekatifa.pdfIn PDF document text
    • http://epoxidice.ro/mm/file/71756710838.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160ccdf714fc34---lexemekosewimuw.pdfIn PDF document text
    • https://isleo.com/i_photos/file/4032418208.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/jfvlskhvt8jr2880d60kogf1ds/negulisif.pdfIn PDF document text
    • http://studioturina.com/userfiles/files/dagimiz.pdfIn PDF document text
    • http://polipack.ru/content/file/gesovezivunewuzosiwokumu.pdfIn PDF document text
    • http://argyler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070733b595e8---26055721933.pdfIn PDF document text
    • http://www.insight-assessment.com/ckfinder/userfiles/files/6601209723.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=pdf+reader+%26+pdf+viewer+ebook+apk+downloadPDF 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_off0000d769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD769 9720 bytes
SHA-256: df1be25b50591b8d6daeb1810ea10d77c1af246f5569ed835745bc0165e76522
font_01_sfnt_off0000ecaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECAF 16632 bytes
SHA-256: 49b5c22735b8d481b48dee92d72bdd739c0cbc044de54dc144c31440651083f7
font_02_sfnt_off000117ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1