Malicious PDF — malware analysis report

Static analysis result for SHA-256 a05df79312ecadd4…

MALICIOUS

PDF

83.5 KB Created: 2021-09-15 12:10:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 07349e78a93420573eb80fa30e48dd26 SHA-1: 815ac66235d2ca0608dd8f1f14296475c7ceef07 SHA-256: a05df79312ecadd421c1f122b943b82cfaa1408a6c20703765e239768d4b1336
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting. The primary purpose appears to be directing users to external malicious sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ros.by/ckfinder/userfiles/files/tevanugut.pdf In PDF document text
    • http://rockbond-aac.com/id-admin/fckImages/file/6703405994.pdfIn PDF document text
    • https://ruta.hu/ckfinder/userfiles/files/33477817123.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/pedugugasowof.pdfIn PDF document text
    • http://vattuxaydunghl.com/userfiles/file/subowubadadanepasigew.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/lndekrpd6303ee2lqc1rque2ld/41397921730.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/14434038704.pdfIn PDF document text
    • https://divinenine.net/userfiles/file/gumewosemanamegobokiso.pdfIn PDF document text
    • https://emons-verlag.com/testarea/cwsCMSlight/media/files/fevopesizofuzedeg.pdfIn PDF document text
    • http://autolavaggiocraparotta.it/userfiles/files/73338486144.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/babowakikujezadajajako.pdfIn PDF document text
    • http://biblioteka-belzec.pl/upload/files/visojukomukizutizulo.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cf92a838dc---modevubujozebul.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/zuvafizuxewesi.pdfIn PDF document text
    • http://megaprestige.ru/uploads/files/36347691976.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/80875779561.pdfIn PDF document text
    • http://esteticka-stomatologie.cz/files/content/file/vegemer.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/dogesukivek.pdfIn PDF document text
    • https://taumed.kz/upload/2021/09files/2109050802205022276vkjs.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161417d4c9cac7---pedegib.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/vebono.pdfIn PDF document text
    • https://rugsinc.in/UserFiles/files/5001813032.pdfIn PDF document text
    • https://foodthings.us/userfiles/file/komunovozikifozibefazez.pdfIn PDF document text
    • http://maekuangudomthara.com/ckfinder/userfiles/files/67521205670.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=icse+total+history+and+civics+class+9+textbook+pdfPDF 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_off0000dfc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC5 11348 bytes
SHA-256: 27b758cc536581d2073dc0bdf3672a2e728794deb68c089f81c11a24026051bf
font_01_sfnt_off0000fa52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA52 17508 bytes
SHA-256: 99d7724708bd245ce49e9e7114b73b3bbc6238cad88689f74aee7f1dacba3779
font_02_sfnt_off000127c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127C7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1