Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b8ab7347b55df3e…

MALICIOUS

PDF

82.0 KB Created: 2021-09-24 01:10:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8d0a342ca4332a9af86b0c92da23e060 SHA-1: c3fc10a8c643c3313c4bad39e00e2509307047a2 SHA-256: 8b8ab7347b55df3e306d993e21c534d179e21128f8808a5d9664813127c4ea58
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to obscure the ultimate destination. ClamAV and the ML classifier flagged this PDF as malicious, specifically as a phishing trojan. The presence of multiple external URIs and link farms suggests an attempt to lure users to external sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://ozkayalarlojistik.com/userfiles/file/63567879691.pdf In PDF document text
    • http://terrietanaka.com/library/files/bawobisidofoxas.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/a9ljaoh6rdjco7i23fq9mma39u/marakavasub.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/20348883154.pdfIn PDF document text
    • http://mskgroup-spb.ru/upload/file/nufukikenep.pdfIn PDF document text
    • https://diedacorporation.net/freesiafiles/file/sasirugofolukamavezakosoz.pdfIn PDF document text
    • https://ytdrive.com/CKEdit/upload/files/41688036335.pdfIn PDF document text
    • https://0800-707-808.com/upload/ckfinder_temp/files/20210912174610.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/62544288727.pdfIn PDF document text
    • http://fairbank-ia.org/admin/ckfinder/userfiles/files/324612819.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16144e99c41b4a---vowitavup.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/33197063465.pdfIn PDF document text
    • https://shirbandifelt.com/userfiles/file/8326928336.pdfIn PDF document text
    • https://ofertaromania.ro/ckfinder/userfiles/files/vazovur.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613c50592e985---75389496646.pdfIn PDF document text
    • http://inggeo.eu/userfiles/files/fexavekuzegewusa.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613656b0af5a9---10018009697.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/masitulogusabexizatatu.pdfIn PDF document text
    • https://lajovisena.com/gallery/file/niluwikeworawowet.pdfIn PDF document text
    • https://firsathosting.com/calisma2/files/uploads/44979377453.pdfIn PDF document text
    • http://ebbers-schilderwerken.nl/uploads/files/jofemunoboxezonixuk.pdfIn PDF document text
    • http://brunagabriele.it/userfiles/files/kekedij.pdfIn PDF document text
    • http://soeurs-scjboran.fr/soeurs/upload/files/99290088565.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/7125138158.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=epub+file+to+pdf+converter+softwarePDF 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_off0000da33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA33 18012 bytes
SHA-256: 61964fafb93373c3f8537e785db202c8f345fa507bedd25351565547d7aae92c
font_01_sfnt_off000108c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108C1 10988 bytes
SHA-256: faae814baad65bbe4fe0b8f291b4ba129b924123bffcdb9e337c31e9dc6220bd
font_02_sfnt_off00012239.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12239 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1