Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a45886b491814d9…

MALICIOUS

PDF

101.0 KB Created: 2021-09-07 19:57:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c6dcc42988b83030ccce655f15f24e66 SHA-1: ef36fdd7dd135f939508610f68c525bed730de83 SHA-256: 4a45886b491814d9ebe087d30f68a3a0b9e21be4e84d02f638c002e36a46493d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with several pointing to compromised CMS upload directories, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and link farm behavior are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9877

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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://2990592.ru/ckfinder/userfiles/files/jefisogib.pdf In PDF document text
    • http://internationalnetworksolutions.net/files/In PDF document text
    • https://chiataiec.com/userfiles/Proj_Name//files/59685886903.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608033c65dce7---sipujejoteponirul.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a2fe10bc5---66998084347.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/810ef5b62f59d06b9abc0578019d7b92/5163420122.pdfIn PDF document text
    • http://mega.kz/media/upload/files/lagamikobejobatiko.pdfIn PDF document text
    • https://samsungvrvklima.com/upload/ckfinder/files/varekemekowijipupe.pdfIn PDF document text
    • http://deaprogettazioni.it/userfiles/files/47384014217.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb5b786568---venugavul.pdfIn PDF document text
    • http://moscowprice.com/content/xuploadimages/file/puxizojupef.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/kkb0frdni2mbdfdf8ac00l4leq/kukanuvapinazozusegonoge.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/4b25131845f327c647eded324b656d1a/xobizuzuvixozurafivuju.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16120b4d9715e0---vabovegobikukubusovoz.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/8eb7ejfrtr253bs8iu8rbikp4d/40041491084.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc13b836be---29838092912.pdfIn PDF document text
    • http://robbinsfamilyhealthcare.com/clients/2/2c/2c787fa606fc56c3a3a24dfc5409695f/File/julibina.pdfIn PDF document text
    • http://hooleihomes.com/cms_images/file/torunez.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/xofowetumoninolaviwiralo.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/nuzapa.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/7818475277.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/gnkfha40nnk1dse3tej87o6tb6/17571054416.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/0tioo275km4kihg8pv78oqss36/11452693194.pdfIn PDF document text
    • http://stardentalcare.org/userfiles/file/49581609382.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9fd0fc28ee---30366381683.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/56224649276.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=tartarini+software+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_off0001232f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1232F 10524 bytes
SHA-256: 8595afd511b557dbdadeb903dd37ea54895ef214512d37f26147627b30f078c0
font_01_sfnt_off00013b41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015353.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15353 18692 bytes
SHA-256: 5d01d4b8b646fd7e7f32041ee5cfbc5b007c3d32f916062be6e2a71678cddbff