Malicious PDF — malware analysis report

Static analysis result for SHA-256 73f399664ba71968…

MALICIOUS

PDF

77.9 KB Created: 2021-09-06 09:36:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 011486c9a616291e5ce29f565c655bb8 SHA-1: fbf4ab71a41d5178e78ee0e5fc435bd5b0f8d7c2 SHA-256: 73f399664ba719683ff1454b567bd7f0f7c145e939f981d39c1534cbb0e60bfd
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many of which point to other PDF files hosted on compromised websites. This behavior is indicative of a link farm designed to obscure the true destination and potentially distribute further malicious content. The ML classifier and ClamAV detection strongly support a malicious classification.

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://fashionflutters.com/ckfinder/userfiles/files/tufor.pdf In PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c0df1526f90---lisexexinazebumogenu.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c33030282e5---ravoninesidatu.pdfIn PDF document text
    • http://brianhaymore.com/images/e/file/228500418.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/riliviwirujenikipe.pdfIn PDF document text
    • http://anoh.net/pds/userfiles/files/kegikurexovina.pdfIn PDF document text
    • https://belloverde.net/emailer/file/winuvirigeze.pdfIn PDF document text
    • http://www.idukkidiocese.org/files/js/ckfinder/userfiles/files/52914507225.pdfIn PDF document text
    • http://kingcraftviet.com/uploads/ckfinder/files/85204697842.pdfIn PDF document text
    • http://trans-serwis.com/userfiles/file/webogasedabuvukosuruwupu.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e59f7e9e34---22427953238.pdfIn PDF document text
    • https://agronlogistics.com/userfiles/files/kavamuralubejara.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/gofati.pdfIn PDF document text
    • http://rucodelniza.ru/userfiles/file/bafizewutezevubas.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/39642471892.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/gonoxomuves.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/buvuwivixeturafi.pdfIn PDF document text
    • http://108homed.com/userfiles/files/73910776519.pdfIn PDF document text
    • https://epiphanych.com/images/file/pijowutasufovux.pdfIn PDF document text
    • http://apcmagon.com/userfiles/jogadoxopixatoxafupu.pdfIn PDF document text
    • https://tonitomov.com/picture/file/dalutezagesopuveri.pdfIn PDF document text
    • http://mastera-mix.ru/ckfinder/userfiles/files/bamuwopifewuxefeb.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/32272946286.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/mkm76ip31i5akfg8gbovnu0bd3/pezudage.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/d0dda02471453fe282c1632aff3354cc/72336963844.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=printable+punctuation+worksheet+grade+6PDF 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_off0000ca65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA65 11380 bytes
SHA-256: 7d5e93e99220b95b8facff02902b7e1e854a92e6563a7ed36f3e14d5175efc5d
font_01_sfnt_off0000e4d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fce3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCE3 17288 bytes
SHA-256: c4c7889c141d7a29ed7d55f3bf79fac303d5aadc0e19443e1f8d3bbb315dc5e7