Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1c31fd40c3a99d4…

MALICIOUS

PDF

69.1 KB Created: 2021-10-02 15:07:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 804bf0ac29a16a331610598ca9f59bdc SHA-1: 47163563f1aa5193423f149b4fa3be9f5f5e430b SHA-256: b1c31fd40c3a99d46a3557047c31447b738292287ba62a8a347d2e18fc0abe8a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. The PDF contains numerous embedded URLs, many of which point to disposable domains, suggesting an attempt to obscure the final destination or distribute malicious content. The presence of external URIs and the link farm heuristic indicate a likely phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://hp-cnc.de/uploads/files/rubexux.pdf In PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/60599509440.pdfIn PDF document text
    • http://rigassprotes.lv/uploadz/file/49365096539.pdfIn PDF document text
    • https://mallncart.com/userfiles/files/38281724212.pdfIn PDF document text
    • http://cherryontop.pl/upload/fotki/file/mepuxolegin.pdfIn PDF document text
    • https://rdw-wolf.de/backend/ckfinder/userfiles/files/19604594072.pdfIn PDF document text
    • http://myredm.ru/uploads/file/metilipede.pdfIn PDF document text
    • http://chornakorn-packing.com/ckfinder/userfiles/files/53377990160.pdfIn PDF document text
    • http://quesnelfoundation.ca/userfiles/file/dewudukugozaxedapujag.pdfIn PDF document text
    • http://kprmk.pl/userfiles/file/59765473613.pdfIn PDF document text
    • https://fancybox.pamlskovnik.cz/ckfinder/userfiles/files/95449797977.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/bidipamogafuwepibopazewuw.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/9m43qf63m0mfl63scrp14f0sko/vamopatezevuloziku.pdfIn PDF document text
    • http://buyo-g.net/userfiles/file/99082869103.pdfIn PDF document text
    • http://ksklinika.ru/ckfinder/userfiles/files/jisekugoxe.pdfIn PDF document text
    • http://cp-1.ru/userfiles/files/23173870601.pdfIn PDF document text
    • http://vdi.vn/userfiles/file/57311060846.pdfIn PDF document text
    • https://12tiga.com/contents/files/zafelogigibolajela.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/89611349708.pdfIn PDF document text
    • http://ozanatalan.com/iboard/includes/userfiles/files/wekisopidevewuze.pdfIn PDF document text
    • https://iuoshili.com/upload/users/files/kixidujabimolulis.pdfIn PDF document text
    • http://palakkadtourism.in/ckfinder/userfiles/files/33458618564.pdfIn PDF document text
    • http://kjphotocon.org/data/userfiles/files/pigazubemejenonuzotapajuk.pdfIn PDF document text
    • http://incomsistema.ru/ckfinder/userfiles/files/zuvoluzidofodakokal.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/kk6kgm941snis3tg4ulephcpn4/fuxariwuxuzod.pdfIn PDF document text
    • https://e-midas.ro/files/file/favezufalixesovew.pdfIn PDF document text
    • http://merklink.nl/site/data/ws/files/roberiba.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=sentence+uses+all+lettersPDF 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_off0000b12d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB12D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c944.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC944 10188 bytes
SHA-256: 6edb8e019dca0eaee6d08b71ab01da805d4a09875e5635c196de3aa0f228eb77
font_02_sfnt_off0000e03a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE03A 14884 bytes
SHA-256: e4584b98bc3cad39cd28625093f1c5dad65ff2aabeee25b8157bd665df0b20eb