Malicious PDF — malware analysis report

Static analysis result for SHA-256 18f9777161c0eef0…

MALICIOUS

PDF

85.0 KB Created: 2021-09-14 03:20:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 4f362adc6df781c3e945196fb0166134 SHA-1: ae1a4682ce26103ac77c4dfebedcea406440b90d SHA-256: 18f9777161c0eef0606136bccc265c032ef7c0dc65fa4a50c06166889556d39c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, forming a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' indicate a pattern of using such sites for distribution. ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious intent, likely to lure users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://pixomot.ru/uplcv?utm_term=game+ppsspp+highly+compressed+5mb PDF link annotation
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe400c964d---kuxajakaga.pdfIn PDF document text
    • http://squash-fitness.cz/userfiles/file/87190481901.pdfIn PDF document text
    • http://mikol-styl.cz/userfiles/file/10303401523.pdfIn PDF document text
    • http://khonggianmang.com/upload/files/66161340517.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210914000118.pdfIn PDF document text
    • https://parfumzone.ro/files/file/23340775.pdfIn PDF document text
    • https://pensiuneaselina.ro/userfiles/file/9456472072.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/78794953533.pdfIn PDF document text
    • http://abwmarlboropike.com/uploads/files/60845666869.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/838f512c7318c53d9203300693b736e8/3352063461.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210914053820_5wgstb.pdfIn PDF document text
    • http://lavalnerina.it/userfiles/file/juxaruwexaro.pdfIn PDF document text
    • https://npkfertilizerproduction.com/d/files/kanano.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-14/20210914052104312719.pdfIn PDF document text
    • http://dominoliberec.eu/images/file/files/waleta.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/kuzetetagiwidonegewufem.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/pivuz.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613fc06af0601---59181754650.pdfIn PDF document text
    • http://bocghebinhduong.com/media/ftp/file/2270931932.pdfIn PDF document text
    • http://asia-test.informacittadino.net/media/files/juzusarokexu.pdfIn PDF document text
    • https://businesslife.com/content/file/21187135183.pdfIn PDF document text
    • https://krzczonowice.pl/gfx/file/sevuneru.pdfIn PDF document text
    • http://oroblupiscine.it/userfiles/files/88083476745.pdfIn PDF document text
    • http://bowlingkillers.com/imgdb/files/xogunun.pdfIn PDF document text
    • 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_off0000e549.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE549 18140 bytes
SHA-256: e3b56ac5b61d2225dd44794ccc9cd6b0b855fce1899e5b02e3d26dd1bcfc0874
font_01_sfnt_off0001144d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1144D 11184 bytes
SHA-256: bd0d2b523b8ba16274eaa42cf79081336e3d836b999763f95d67c92c2c39243d
font_02_sfnt_off00012e1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E1C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1