Malicious PDF — malware analysis report

Static analysis result for SHA-256 4780ed20fee59ac4…

MALICIOUS

PDF

95.4 KB Created: 2021-07-03 01:38:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 17605a1e09384f611bfc1f7c6e7e4c0d SHA-1: f8e3cb07df7f3eba5d4d80846e9de9569f1cb1f7 SHA-256: 4780ed20fee59ac49ffd394a3e827dc9ed074b3c29f1235ce9cd7f0c3a7cc45b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs pointing to various PDF documents hosted on compromised websites, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for SEO manipulation or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or content distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://bouwservicewinthagen.nl/userfiles/image/file/89413839456.pdf
    • https://zegabilisim.com/calisma2/files/uploads/pebupumikudivafuresabuwel.pdf
    • http://vdadanang.vn/app/webroot/assets/files/vafujowuxadoxaxed.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b23879e976---bagezajamisik.pdf
    • https://englewoodgrassfarm.com/wp-content/plugins/super-forms/uploads/php/files/ba02fe27ca53d5120d424aa246703102/49767250964.pdf
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/n4i558ikm2ph73vkkr5ff1ck92/bujaner.pdf
    • http://porpora.info/imagenes/imagenes_contenidos///bezikozifas.pdf
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/1a2590b5f0264131fb64d08ee1016017/10853660554.pdf
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/lizuzeje.pdf
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/c8646054b6585d4e18b0d26f906c28d0/vizaxomaro.pdf
    • https://getadoc.in/ckfinder/userfiles/files/jagobarepodotaxixemewox.pdf
    • https://girilawfirm.com/content_files/files/76487243003.pdf
    • https://media-get.ru/userfiles/files/45765332284.pdf
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/q3q901ociuo8u5104cand16q9a/34119113932.pdf
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/fd3c8f18fde2358616b70c4fd97067b5/fudurirobinelopomituf.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a498898fb68---84534934699.pdf
    • https://locktactyuma.com/ckfinder/userfiles/files/56843343017.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086b2baa81c8---99382973639.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0b79628b1---66341922944.pdf
    • https://systematix.pl/userfiles/file/zeluvasovuja.pdf
    • http://slippersymposium.com/clients/875641/File/vumebozajavewevinivusima.pdf
    • http://hyundainhapkhau.net/upload/files/80060499538.pdf
    • http://loveperfectionschool.com/upload/file/69685429835.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d275315725---94312558039.pdf
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/ac55da5dc3fd50f9935fb5b601122f28/kekelukolumujawivevagif.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=photosynthesis+is+not+affected+by
    • 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_off000110da.bin
cd95c3f83ea13706d7466a797bf43ca8456b39402bba674c2b6e5e5643299be4
pdf-font-stream PDF embedded font (sfnt) at offset 0x110DA 10684 bytes
font_01_sfnt_off00012959.bin
cb4ce9557b0ad6a6d5cd6640540cb98730e16f44b98348754934aed696ba4782
pdf-font-stream PDF embedded font (sfnt) at offset 0x12959 18324 bytes
font_02_sfnt_off00015811.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15811 16792 bytes