Malicious PDF — malware analysis report

Static analysis result for SHA-256 5943fb6f649ecfff…

MALICIOUS

PDF

85.4 KB Created: 2021-09-12 02:22:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0400ddd139ba7edfcef576ba8e5d4fee SHA-1: efc777fba81d32f10fc8e3b10e0397ec701e850a SHA-256: 5943fb6f649ecfff2c479907bd24c84b114b1442003e095674ea2a2c8c802f40
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are identified as part of a link farm hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The embedded JavaScript is likely used to facilitate these redirects or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=handshake+app+for+android
    • http://ekmeta.lt/failai/file/10754468828.pdf
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/88928378203.pdf
    • http://samajsutra.com/userfiles/files/rifajove.pdf
    • http://www.hro.ait.ac.th/js/ckfinder/userfiles/files/17379946074.pdf
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/391a96e9bbefb4360335c8ecdc0d068a/fabajovedusawe.pdf
    • https://ipssecurityconsultants.com/ckfinder/userfiles/files/68890064344.pdf
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/kqb2bql4e9qeb2e0gosloaab34/73189244726.pdf
    • http://namhungholdings.com/uploads/ckfinder/files/35836660280.pdf
    • http://cascinamana.it/userfiles/file/60093416875.pdf
    • http://integrotech.com/zdjecia/file/82843480681.pdf
    • https://e-room.co/userfiles/file/49002101611.pdf
    • http://johnlillylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/juvitetowix.pdf
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210908_4FD0BA4FE5A4B3E0.pdf
    • http://gesgo.de/userfiles/file/tubuworinid.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613d246895d94---47445866528.pdf
    • https://lifeteacher.tw/uploads/files/202109061425444685.pdf
    • http://canshu.dlzj.net/upload/files/20210910011457878646.pdf
    • https://www.domaine-vrignaud.com/ckfinder/userfiles/files/51854922827.pdf
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/161394584c9126---wasexazupupekepimaburopej.pdf
    • http://thietbibepnhahang.net/media/files/juxatox.pdf
    • https://laplacedesstores.com/upload/file/ginuvakejaxabiguwip.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/161317a5dbb053---jokajivovoxisobumefilo.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/iio0hgvhkdgaod2di8dimvsui3/budetugabi.pdf
    • https://kurtoglumob.com/upload/file/58505476411.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea30.bin
defb5f99a2e0854c4082edb28c1c0f487f92a437bff964f3132589bd95c0deb0
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA30 10532 bytes
font_01_sfnt_off000101ff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x101FF 16792 bytes
font_02_sfnt_off00011a11.bin
a623ef1ff56eccab453e09c3a34f5f1e681cec69ce0634d611fa3a5ad5a49f7d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A11 17936 bytes