Malicious PDF — malware analysis report

Static analysis result for SHA-256 d85bfea1810bc892…

MALICIOUS

PDF

86.0 KB Created: 2021-08-09 00:50:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b0876ebcbb6f2d50398deb775879fff4 SHA-1: d15153f69ccedfabf30b7052db6347d735dc39cb SHA-256: d85bfea1810bc8920dd3741d56335493d9de780bb3be2673d25b7603fa15cb65
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to numerous distinct hosts, many of which appear to be compromised or disposable. The primary goal is to redirect users to potentially malicious content hosted on these sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://kursadowicz.pl/Upload/file/6809289207.pdf In PDF document text
    • http://nt-module.ru/ckfinder/userfiles/files/pukawijenoladakikas.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/68941685683.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/843c90c6b839b1f870bb48caa6a01ddf/puwag.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/160753e2f08105---farutipisidixozako.pdfIn PDF document text
    • http://actybrain-consult.com/Upload/files/fulefigexirebivokif.pdfIn PDF document text
    • http://cornucopiafrederick.com/uploads/files/9100247871.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085ebad85e72---89929676134.pdfIn PDF document text
    • http://design-klasse.de/ckfinder/userfiles/files/tuxafiwam.pdfIn PDF document text
    • http://quocteanviet.com/img-chamthi/files/71383755784.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/litujun.pdfIn PDF document text
    • http://vasset.bg/userfiles/file/jitaxumifebenilovezepefap.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160e0248a23cb1---lepog.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/b79336045828a9e58ded8af29b0df354/7147890133.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/ef4a15180c2e6487d834b5aa3174ad3c/47783849731.pdfIn PDF document text
    • http://fst-uinsu.net/userfiles/files/wuganoleneludazaru.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609525f2a8be0---77622076465.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/bapadu.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/ziwatu.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/pewevuke.pdfIn PDF document text
    • http://vistobrasil.net/uploads/file/kifemuzimajoronupudena.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/jiwavuxigomufuliwe.pdfIn PDF document text
    • https://blogsma.com/files/wulujonapax.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/pq289jei1hdqp2hsdp54on71d3/seporupe.pdfIn PDF document text
    • https://dolaodong.com/userfiles/file/fejerememorulegovalu.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fa967a886ac---62085632503.pdfIn PDF document text
    • http://mirutte.com/newsfiles/files/45332330251.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=black+capped+chickadee+songPDF 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_off0000ebf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF3 17588 bytes
SHA-256: 9e9b10d47f4eac35d1465f3004debce6772898ad7fb2a6da35f849e7cd992658
font_01_sfnt_off000119da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119DA 10740 bytes
SHA-256: 70a4c9a6c375fad82eaa25f712529cea81b6a1b6dcc9cf6015ba29eac8d70b07
font_02_sfnt_off00013245.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13245 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1