Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f5f86400e7d8234…

MALICIOUS

PDF

86.4 KB Created: 2021-08-10 14:38:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: bc541d0784a19bb429ce8fa4701b2ae7 SHA-1: e9994b82e3ca8cc18e531339855edff2880b2d52 SHA-256: 3f5f86400e7d8234fb58376dd327fcdb883fc23fdb1d4177b97bf1160669f87f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is designed to redirect users to phishing or malware-hosting sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://ketchas.ru/uplcv?utm_term=how+do+i+get+my+old+california+driver%27s+license+number PDF link annotation
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608049f4d9be8---foxodo.pdfIn PDF document text
    • https://semagro-msw.ru/pics/images/file/pagako.pdfIn PDF document text
    • http://k-souz.com/userfiles/file/5124046129.pdfIn PDF document text
    • http://monroehighwildcats.com/clients/40160/File/8323824659.pdfIn PDF document text
    • http://mmcaana.com/clients/29274/File/20081517543.pdfIn PDF document text
    • http://ivepe-elearning.gr/assets/UserFiles/mainHome/file/fuvez.pdfIn PDF document text
    • http://bio86.fr/fichiers/50004205731.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/5719665457.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/fg4rgo1ur4geog4pbf94nnpl3r/87775551370.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/d7c5d05ca6b3561eb3eb38ece8a9a099/42702906362.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/gibuzi.pdfIn PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160967b5394543---65399439757.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/o0cdead5lvooqpm5oke5mr2vh4/nokegu.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/b0hmgaaurq37ofpoktco26erjb/juvajimamewijawokigu.pdfIn PDF document text
    • http://tlumacz-bialystok.pl/pliki/file/dizasesemate.pdfIn PDF document text
    • http://emeraldcovepartners.com/_data/images/file/55006828309.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/fenojori.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/uklgg3ac3mnrh3mbnp09n9vip4/89718689732.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b220c8e69aa---68101959713.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984a49cdadd---kuborumugeturozikogadolar.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc6b577e25---85824763476.pdfIn PDF document text
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/37434e55c7519975581d660d6fa98ec7/taxuluremetijos.pdfIn PDF document text
    • https://hagakure.by/upload/editor/files/75437316603.pdfIn PDF document text
    • http://stalmost.pl/userfiles/file/maxofimegib.pdfIn PDF document text
    • 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_off0000ec1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001042f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1042F 17308 bytes
SHA-256: f7bfa6239b6f06346901f84badb52b1ee6fc3762bfb40c7831b5c27b0b7f3b67
font_02_sfnt_off000130bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130BB 11348 bytes
SHA-256: 4e0f80b5d1d0f17d30303a4c997130a83b7d486c76f61c9a03d9d4bbda9d54b5