Malicious PDF — malware analysis report

Static analysis result for SHA-256 79bd9a762ad527c4…

MALICIOUS

PDF

87.4 KB Created: 2021-09-21 01:01:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2b9bb0e76c35cb289a9b991620970d18 SHA-1: 92d47e15ab058a999273fc6872a4679946c80a94 SHA-256: 79bd9a762ad527c4aeb62fd0d1986c5472520042fab0815da541a83cb977eab9
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous URLs pointing to compromised WordPress sites and disposable domains, indicating a link farm designed to redirect users. ClamAV detected this file as a phishing trojan, and the ML classifier strongly agrees. The embedded JavaScript likely facilitates the redirection or exploitation process.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=best+subtitle+maker+app+for+android PDF link annotation
    • https://nsstore.mx/ckeditor/ckfinder/archivossubidos/files/tovaxaxubasi.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/hged44u5vdhsgvnf6pmru8ku00/3288601705.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/60151220111.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/8b3efe7c1c0a3cfe1127f724e5748aaf/pipinerasijuba.pdfIn PDF document text
    • http://limeitec.com/upfiles/editor/files/lunepobobuvofobukav.pdfIn PDF document text
    • https://wroclaw-effatha.pl/grafiki/file/84491730479.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/pfu02b6jc01r3m84h2ai6ol59j/pimovagatudapi.pdfIn PDF document text
    • https://www.q-jin.ne.jp/ckfinder/userfiles/files/mepuwotadapapenizinokava.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/18223492036.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135f397a92ad---majoribisiva.pdfIn PDF document text
    • http://art-ball.net/files/file/63669138427.pdfIn PDF document text
    • https://goacetours.com/ckfinder/userfiles/files/dovizi.pdfIn PDF document text
    • https://digbijoynath.in/uploads/userfiles/files/palonedada.pdfIn PDF document text
    • http://www.performhabitat.fr/bundles/astadmin/js/ckfinder/userfiles/files/sefapuxiponowimodusiviki.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/e263ed72b038dab77f13cb598be9ee50/nupurenitoxetonoxowakep.pdfIn PDF document text
    • http://geo-equipe.it/userfiles/files/jenuwuribofuxikuwiranenu.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/53vmgq2grsha0ab871s1hc6ed4/tugogovudujeliledimavar.pdfIn PDF document text
    • http://heydarbaba.org/resimler/files/98140701114.pdfIn PDF document text
    • http://bndweb.nl/upload/files/14618773045.pdfIn PDF document text
    • https://aslplastic.com/ckfinder/userfiles/files/99930489233.pdfIn PDF document text
    • http://sinice-rasy.cz/files/file/jupuwidofo.pdfIn PDF document text
    • http://liceoadultos.juniorcollege.cl/userfiles/files/89908233783.pdfIn PDF document text
    • https://abriganature.centralcms.cloud/galeria/files/42166443846.pdfIn PDF document text
    • http://an-ocn.ru/ckfinder/userfiles/files/82578364114.pdfIn PDF document text
    • http://ownlines.com/upfiles/file/32399335635.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_off0000f137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF137 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001094e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1094E 11044 bytes
SHA-256: 89cdf7920c48782bfce31f104c775ad3fcb5a1705939220ef75afcf34248f1ec
font_02_sfnt_off000122c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122C6 17768 bytes
SHA-256: bc4255f75dac227e0ac07f862a418ec86f6b4f53ad6b77f960ba77dbc6c44f93