Malicious PDF — malware analysis report

Static analysis result for SHA-256 6de81ae19916281c…

MALICIOUS

PDF

82.9 KB Created: 2021-09-10 09:13:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 49297478fb53f4fc52c65edd24e153fc SHA-1: 428248f8ba145cda4da003d1eb5e8310aed62a54 SHA-256: 6de81ae19916281c36c4633a9ec80b18c1fc3a7b5bec21b87b24348ee077b8da
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The file contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, suggesting it is part of a link farm designed to redirect users to malicious content. The presence of external URIs and link farms indicates an attempt to lure users to potentially harmful sites.

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://nomylo.ru/uplcv?utm_term=best+music+app+with+lyrics+offline PDF link annotation
    • http://speckrepej.com/upload/file/84350393889.pdfIn PDF document text
    • http://modaxch.com/userfiles/files/65844882141.pdfIn PDF document text
    • http://morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613265f734ddd---wubugaxuxopujodigobuf.pdfIn PDF document text
    • http://cyuanmei.com/userfiles/file/funilajotuvoxiwejado.pdfIn PDF document text
    • http://dostrojar.sk/UserFiles/file/noboju.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac2e3359e8---68957772614.pdfIn PDF document text
    • http://kwong-cheong.com/userfiles/ligisonag.pdfIn PDF document text
    • https://www.naabelectric.com/userfiles/files/53474901586.pdfIn PDF document text
    • https://ltes.tw-goods.com/UserFiles/files/90953809577.pdfIn PDF document text
    • https://vnycc.com/userfiles/file/12832970172.pdfIn PDF document text
    • http://brickchamber.com/ckfinder/userfiles/files/46067258276.pdfIn PDF document text
    • https://dom4m.lv/userfiles/files/zukifopizupemo.pdfIn PDF document text
    • http://mim2010.ru/userfiles/file/bodusesumaranadeziwod.pdfIn PDF document text
    • http://irths.com/upload_files/files/sevol.pdfIn PDF document text
    • https://ietc-oman.saktoon.com/userfiles/files/54972208488.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013/admin/ckfinder/userfiles/files/35479466915.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210907_495969BABA0EA06F.pdfIn PDF document text
    • http://tw-jia.com/uploads/files/202109060329291615.pdfIn PDF document text
    • https://branchennachweis.eu/userfiles/file/matopipigiwuwimawefopo.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/68881223312.pdfIn PDF document text
    • http://maremania.net/img_pagine/file/76898601244.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613aaeb88b96e---77622487432.pdfIn PDF document text
    • http://3gr-group-com.gbintl.com/ci/userfiles/files/69746910192.pdfIn PDF document text
    • http://kangmeideyiliao.com/uploadfile/file///2021090507513754.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_off0000ddd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5EB 17776 bytes
SHA-256: 9240a24c02049772881849988f9904e3ae2e426ef45e2d4837c4a4c39a732bcd
font_02_sfnt_off0001241c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1241C 11100 bytes
SHA-256: 2efa654fc09d8551a3b15a6a178f62a50102da849011c80686581956f698e598