Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc96d1f68435fb1f…

MALICIOUS

PDF

68.6 KB Created: 2021-10-20 22:07:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 0392dedd8c9af416915c7c63345fb34a SHA-1: 632a4a221be20842451ba6dc3d06c24498efe481 SHA-256: dc96d1f68435fb1fc3a2f8dc1e9be488616f610623628ee4b6f17c0dc31940a6
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. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, forming a link farm. The primary function appears to be redirecting users through these links, likely to a phishing or malware distribution site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://ocvitlucky.com/vietkiendo/upload/file/waximuj.pdf In PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/161603291e5d58---woforasageg.pdfIn PDF document text
    • http://aibasylhet.edu.bd/app/webroot/ckfinder/userfiles/files/47566380881.pdfIn PDF document text
    • https://gabconstruction.com/ckfinder/userfiles/files/duturasafetajote.pdfIn PDF document text
    • http://eggtesting.com/admin/uploads/file/fepufejovofuvomomapi.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/vk3mrk218e63kj9oqqitp1c02l/85227021562.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/puwejavorokimi.pdfIn PDF document text
    • http://luckysim.com/userfiles/file/mebusalotisuz.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/podakepifumovofilenapuzu.pdfIn PDF document text
    • https://bakwanudang.com/contents/files/93205441116.pdfIn PDF document text
    • http://weorderfood.com/uploads/files/15888587113.pdfIn PDF document text
    • http://motopujcovnateplice.cz/userfiles/file/94295849537.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/2489849352.pdfIn PDF document text
    • http://ser-buk.com/userfiles/file/todumo.pdfIn PDF document text
    • https://phatgiaolongan.com/upload/ckupload/files/xusen.pdfIn PDF document text
    • http://onroerendgoedindex.nl/images/uploads/wenitusapupij.pdfIn PDF document text
    • http://ihanzao.com/userfiles/file/20210921010059_383792489.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/netewejoz.pdfIn PDF document text
    • http://etspak.com/survey/userfiles/files/fanukofagijituwixaraxem.pdfIn PDF document text
    • http://xedaphcm.com/luutru/files/gegavuxejepemexizak.pdfIn PDF document text
    • https://efsanepin.com/calisma2/files/uploads/golesokotanadise.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb2fce43ba---mogolu.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/sonogijoxesunimige.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/BGAemAmcdTc/uplcv?utm_term=how+to+convert+weight+into+poundsPDF 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_off0000af2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c741.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC741 10828 bytes
SHA-256: 610173fd6285478500a0dea5289e2898675ed80b3d1eb7192343fea88d7a3060
font_02_sfnt_off0000dff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFF6 14692 bytes
SHA-256: cc6fbca2f53cab809a284c37df2711e9333ad197b745692351eec2fc4e477365