Malicious PDF — malware analysis report

Static analysis result for SHA-256 553b726d850fbcd4…

MALICIOUS

PDF

83.2 KB Created: 2021-09-04 04:16:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b0e1c7c44f1c9617935cf1810eced27e SHA-1: 4de810d0c423828d65b08785965cbfe31f947b7a SHA-256: 553b726d850fbcd4aea4b12b28832b4d1c86f7bd5d0c9d45375b1d66ba956874
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to redirect users to malicious sites or download further payloads. The presence of numerous links pointing to compromised WordPress sites and disposable hosting further supports a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://rotitelor.com/contents/files/47935190954.pdf In PDF document text
    • https://ibeguiristain.com/userfiles/files/defokiv.pdfIn PDF document text
    • http://travisreunion.com/clients/1/1d/1d9c560ef9ee6310b862f4c9d288d7bd/File/20817531833.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///94816770006.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/f3bcc0104534fa0d2f5c4868862e71f0/68435967797.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/5dd4d4b34bf38b7a9dfc4e39274204df/koxunukodusugedafukiwefor.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/tebalirakepezi.pdfIn PDF document text
    • http://mytaylormadefamilyusa.com/clients/864113/File/38524600015.pdfIn PDF document text
    • http://klinikoral.com/img/userfiles/files/fevufog.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/01e8451240d19407127a3fee2dbbc15f/62783630327.pdfIn PDF document text
    • http://mindentudor.hu/userfiles/file/55150563171.pdfIn PDF document text
    • https://sfasg.jp/js/ckfinder/userfiles/files/jasebaterutape.pdfIn PDF document text
    • http://euredit-editions.com/userfiles/file/volanunewaripikilana.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160c64df1f2e7d---vemipupivukutukajej.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/aviffp8jbsvioafjrb5qe3im30/54262547910.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///dafoxepozifepozaluzo.pdfIn PDF document text
    • http://emilygrilltogo.com/uploads/files/bidonefirup.pdfIn PDF document text
    • https://efficientinfocomm.com/ckfinder/userfiles/files/99165242594.pdfIn PDF document text
    • http://kezheng.net/Upload/file/76919221085.pdfIn PDF document text
    • https://manuscripthandler.com/userfiles/file/ligikij.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/a10377c1479fe1edef4021c1d4e6557b/43422181814.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/be76ae8ff2d57ffdc7819567d3c9b971/nunaxeloxig.pdfIn PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/5396378617.pdfIn PDF document text
    • http://parkhighclassof60.com/clients/871169/File/5461281557.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160775906781de---jipawafizixa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=aws+sample+resumes+pdfPDF 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_off0000e0e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F6 17972 bytes
SHA-256: ea0b1f41f56dcbc0d3c77be5c5ce54ffa581dd561aa70ab8295d8b24898f91c7
font_02_sfnt_off00012788.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12788 10412 bytes
SHA-256: fdb965ec0799b5d67f53db40794c0c4eb37597e0ae398f7bc1c5bc823b765c24