Malicious PDF — malware analysis report

Static analysis result for SHA-256 98561990ded0c9fc…

MALICIOUS

PDF

81.1 KB Created: 2021-09-05 04:55:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 035704919c7bcad1bce610af805d93cb SHA-1: 583690796049f5e13189f84db474ebdf4ea747f3 SHA-256: 98561990ded0c9fcfd0027c780c7654ab8277c3e8de8ffe709becd60ad966ef7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS uploads or disposable hosting, suggesting an attempt to lure users to malicious sites. Although no scripts were extracted, the nature of the links and the detection names point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://akcjonariusz.com/UserFiles/file/povij.pdf In PDF document text
    • http://calzaturificiocatia.it/userfiles/files/5837896730.pdfIn PDF document text
    • http://vzwsportenmuziek.com/content_docs/72983249502.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/83ab3d5bc4e0e39ae08a7d75caa161c6/lenipufuxuboderedow.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160831cc590b8a---32842407664.pdfIn PDF document text
    • https://pediatricpotentialsnj.com/PP/PPpng/files/zazomix.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3861d3fd11---jigesujidakemokuru.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16075f59097921---simisukanuviwubuxewolad.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/o845kiru2at2p2tkhui8p5ufj6/42580424032.pdfIn PDF document text
    • http://inhome360.ru/admin/ckfinder/userfiles/files/22548894640.pdfIn PDF document text
    • https://mkart.it/uploads/file/3963908365.pdfIn PDF document text
    • http://nkmate.com/FileData/ckfinder/files/20210815_DCAE1067A530472D.pdfIn PDF document text
    • https://birudongker.com/contents//files/27788656574.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/st20rpr8nemgmh88pd5helb9kl/vilusovijitalegezag.pdfIn PDF document text
    • http://harissarantis.com/userfiles/files/nogewetagevadovobax.pdfIn PDF document text
    • https://mimpiindah1.com/contents//files/50075896182.pdfIn PDF document text
    • http://istanbulballoons.com/ckfinder/userfiles/files/55558122014.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/pokejabaxixuge.pdfIn PDF document text
    • https://ariconium.cz/webpagebuilder/ckfinder/userfiles/files/wugoxukogukexafemo.pdfIn PDF document text
    • http://areawifi.com/DESARROLLO/userfiles/files/1018350881.pdfIn PDF document text
    • http://bilmatbasim.com/userfiles/file/tepupabile.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=14+kebutuhan+dasar+manusia+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_off0000db93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB93 16384 bytes
SHA-256: ee2826cc97ff2647c9ad1745cb7a8df41d9aa160cd8358fff6aaeea5e3d2cdb5
font_01_sfnt_off00010567.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10567 10960 bytes
SHA-256: 9658c4fdbae6c6cd420c02d5019e5518153e52c45d2b65f28dc7388d9c978a0a
font_02_sfnt_off00011e75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1