Malicious PDF — malware analysis report

Static analysis result for SHA-256 91e1253d54a08c9d…

MALICIOUS

PDF

74.6 KB Created: 2021-09-03 06:48:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7fdd0755f7be26d509a7daecee59068d SHA-1: 43c24bd642b0c332865e05764e7250b19f75f4e1 SHA-256: 91e1253d54a08c9d151abf9cf5f05be87ad72b255adcc7c06be52dd6e4a36710
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, which are likely part of a link farm designed to obscure the ultimate destination. ClamAV and an ML classifier identified this PDF as malicious, specifically flagging it as a phishing trojan. The presence of multiple unknown URLs suggests an attempt to distribute further malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608667409ec38---loguvelasuluwapiwomexosol.pdf In PDF document text
    • http://teplo76.ru/uploads/file/85125941782.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/2bi00fkkfu2pisthm3gqim56b4/dabazatisukirixokul.pdfIn PDF document text
    • http://siciny.pl/userfiles/file/97576221807.pdfIn PDF document text
    • http://moskvaznaet.ru/upload/files/fafufegexikigowod.pdfIn PDF document text
    • https://dubaimotorcycletours.com/uploaded_images/files/duxezavazewakovepifipus.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/repemunogafetoram.pdfIn PDF document text
    • http://facyt.com.ar/ckfinder/userfiles/files/fusawavurezoxuxuf.pdfIn PDF document text
    • http://projecthouse.bg/uploads/CKfinder/files/mogakupegapolulo.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/11976658177f501fdd72ee7913df4428/gajezodubaxif.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/gojunatedakite.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/8rt031lgtf79cq76s9jdbm69d2/xaguvupu.pdfIn PDF document text
    • http://ozanatalan.com/iboard/includes/userfiles/files/91466116110.pdfIn PDF document text
    • http://mths1965.com/clients/6/62/626de2090e8268457c7577d5e8b87900/File/kebibo.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/livijofisowixa.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/51127292660.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/5d6aa6e94161a9f2abda2fca9d410ef9/wudaxaxikusejalifawinar.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/dezurafinuxozepaton.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/69615753753.pdfIn PDF document text
    • http://assytekservizi.com/userfiles/files/zukubawivaworujelepudizid.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/84475052529.pdfIn PDF document text
    • http://szpital-sulecin.pl/images/fckfiles/file/loxatarewusewi.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/15939407900.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/13439051454.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=leucemias+pdf+pediatriaPDF 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_off0000c2e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2E5 16316 bytes
SHA-256: 0d2780cded1ef215b383e9d716fc9dc97a6491ed6b3e363884592808cf12d198
font_01_sfnt_off0000ecb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104D0 10568 bytes
SHA-256: 4cd63febe0da864d925cb6a122ffd00c003dcfb6890c82497fc9047004f6ee98