Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cd1cb52e47464b1…

MALICIOUS

PDF

97.0 KB Created: 2021-09-24 02:49:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 75ec26bc781dc5136eefc97b0fc390c2 SHA-1: cc78e81edbca1bd32e8482b31d18af214fb980a6 SHA-256: 7cd1cb52e47464b1e352c4f3500c901439f4a045ef69db3d9b7f9b762bb68c3e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicative of a link farm. The presence of embedded JavaScript and a high ML classifier score further suggest malicious intent. ClamAV also detected this file as Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9927

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://szwygs.com/upload/petakigorerinu.pdf In PDF document text
    • https://egyiksem.hu/uploads/file/sanefasodiged.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/g0iiqddmibpj5pj9dd93rh96q2/dezikiverajozamimofijosof.pdfIn PDF document text
    • http://hakasasi.id/userfiles/file/gexajopok.pdfIn PDF document text
    • http://sheilahancock.net/blogfck/file/16609765253.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/33149822740.pdfIn PDF document text
    • http://hotdeals24x7.com/ci/userfiles/files/37870734282.pdfIn PDF document text
    • https://sergiomauri.com/images/file/65448636582.pdfIn PDF document text
    • http://ktcyy.com/ckfinder/userfiles/files/poxomi.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/161369aed0e01d---39034055791.pdfIn PDF document text
    • https://xaydungkienthiet.com/upload/files/80711391756.pdfIn PDF document text
    • https://estatecambodia.com/htdocs/cljr/data/files/bimasosovixu.pdfIn PDF document text
    • http://autofactory-jin.com/js/upload/files/64957539943.pdfIn PDF document text
    • http://anoh.net/pds/userfiles/files/12277936698.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/a17368aabc575a0199bdbb331f8ac656/rudedewurikaxi.pdfIn PDF document text
    • http://pileki.com/imgup/file/xadawazibesigo.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/76574811478.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/vudowagozot.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/08234ec6b038e5b2cb307e796e63e310/duziku.pdfIn PDF document text
    • https://nirmalujjwal.com/public/ckfinder/userfiles/files/28470739576.pdfIn PDF document text
    • http://tischtennis-kiel.de/images/file/27811565389.pdfIn PDF document text
    • http://zehanbiopharma.com/upload/files/xazasa.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/masuju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=gta+chinatown+wars+save+data+androidPDF 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://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_off0001194d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1194D 10612 bytes
SHA-256: 08a9fc41f45ba4fe6e681d489d4d168069ab57ab1dda66a23d506f1d50e68bb5
font_01_sfnt_off000131a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000149b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149B9 19004 bytes
SHA-256: fd73ca035e13c5f78fa354250fc5157c34f621ca62ff7c56b67d406ce04e0878