Malicious PDF — malware analysis report

Static analysis result for SHA-256 a16b539787a3f7d7…

MALICIOUS

PDF

107.5 KB Created: 2021-07-14 04:07:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: b89b7f38b93761c6b778577f49ece75f SHA-1: 0274cd9349e6fd1022f4e084d1866510a7a44933 SHA-256: a16b539787a3f7d79c6ab8009e0c6d28da6906e3a450d7785094d1226a0f1043
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to lure users to malicious content or phishing pages. The presence of numerous external URIs and the nature of the links indicate a phishing or SEO poisoning attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9780

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://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a787ce0339c---lusetesegesatigasoseru.pdf In PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1606dd3ba99be8---kikofakimonepifugijenuwi.pdfIn PDF document text
    • https://tonitomov.com/picture/file/gakivivapipozi.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/megavurovuwinabuporuz.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/db53a9c277622fc55d8e7055d23cc1f4/16266739559.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082fe6b67110---95720230042.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/lrml9h182f0d61qsiakr4ocvfc/73311511925.pdfIn PDF document text
    • https://kermoulin.com/userfiles/file/mazixenupevirerobopowup.pdfIn PDF document text
    • http://gayaarchi.com/userfiles/file/20210628030636.pdfIn PDF document text
    • https://cncunse.com/d/files/lozafopili.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a4daf00a191---62571236559.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/soluzozo.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/47018b34962200f95c2e6864e48cb229/ralagobawudufok.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160dd73b36e68f---82331308236.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/sr1u623bkp7mrvrpdv8h2ampif/90855951299.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078bef5bf5cd---nuxafotunadidatojudala.pdfIn PDF document text
    • http://www.oiseaubleu-promo.fr/userfiles/file/pesib.pdfIn PDF document text
    • https://htchninc.com/d/files/ditoxeborof.pdfIn PDF document text
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/5524889b19033907060df657541f48c0/moripef.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b402bfca3ec---31887585291.pdfIn PDF document text
    • https://steklo-shik.ru/userfiles/file/bibogitususiwelunepizuli.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/61703241556.pdfIn PDF document text
    • http://www.bandungmesin.com/file/givezakodofupatodi.pdfIn PDF document text
    • https://mmszke.hu/files/file/82365377416.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b96c7fb6f72---tanasovafizajofukite.pdfIn PDF document text
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/tjeiedv9ul6oqet31k1uk707bq/37707979086.pdfIn PDF document text
    • http://bogelaipigeon.com/upload/file/nupazixumuvogun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=pink+and+neon+green+hairPDF 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_off000144b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x144B6 10308 bytes
SHA-256: b45c93a853547c742cff3bc3426aef7d11213760796974847533497bad32d63b
font_01_sfnt_off00015b93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B93 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000173a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x173A5 17284 bytes
SHA-256: 7a64b4f873bf2d0717865fbfc8fa9608c97b46df0d235ec7549546be3a2e8474