Malicious PDF — malware analysis report

Static analysis result for SHA-256 e55df3bcfcedd53f…

MALICIOUS

PDF

72.9 KB Created: 2021-09-03 19:02:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 8a3073e9f28ddce9d910bb40500a333d SHA-1: 9a3def0ae9261a0d1214176f28eb0593f4bbd693 SHA-256: e55df3bcfcedd53f1ef3d369b1c5b1e746648ca9ecde09d30876a1b511247e0c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a significant number of external links, many pointing to PDF files hosted on compromised websites. This structure strongly suggests a link farm designed to lure users to malicious content, likely for phishing or further malware delivery. The ML classifier and ClamAV detection further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://transchem-tech.com/Uploadfiles/files/vubanuwul.pdf In PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/norikobuvoti.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/39lj7hb0k2mf38cq3lojftdrrb/84352774169.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/q391ppk757nd26rfdrio8v0p40/tipogevebixuvi.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/vitakidugexelu.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/52c4065c584e087461a3042531bab834/gemejis.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/zawewili.pdfIn PDF document text
    • https://eastmanllc.com/ckfinder/userfiles/files/26909708472.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/wekovajazobu.pdfIn PDF document text
    • http://ks4073.com/file_media/file_image/file/3890326640.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/voliwirox.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2adbe18af---magerularetijoxa.pdfIn PDF document text
    • http://kaies.net/upfiles/file/juvol.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607d356289237---foxirisejepefolow.pdfIn PDF document text
    • http://akgwealthplanner.com/crm/files/mibuxavad.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adabb88cb10---muven.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/8b3e00ee7ed83a5b067da129d16a0551/17543712882.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/f40bf1dedb221aaa5c27dd89b2bb8192/zisilas.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b602a8d019c---zebirilubibotejukigokiguf.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/39550505822.pdfIn PDF document text
    • https://west-holding.com/userfiles/file/fixofasave.pdfIn PDF document text
    • https://chasehr.in/userfiles/file/42124920512.pdfIn PDF document text
    • http://shortguycentral.com/ck_uploads/files/filoj.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/ce97e7ca84d5a6edd78ec03e801126f4/86836405604.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=sandstrom+bluetooth+mouse+manualPDF 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_off0000b9a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9A6 17176 bytes
SHA-256: 44304a3fd18450bee48f4229c5dcdd2655fe629dc719bdad189d8af798256aef
font_01_sfnt_off0000e60b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE60B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE22 10736 bytes
SHA-256: 932599415ad2cf813552f7b81058b4eb1db04fa560181d03125a8bf8578a9c50