Malicious PDF — malware analysis report

Static analysis result for SHA-256 824f296be0712342…

MALICIOUS

PDF

82.2 KB Created: 2021-09-01 12:20:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 54e5760c8dc103b13874278c0ebe53b3 SHA-1: 3c9268c9f34c3da592a4bf6b183f5b10aac51309 SHA-256: 824f296be0712342bc0fda179b6f4c04c7a5ff59f4dfb5f98f26eac2ab912bb9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to distribute malicious files. The presence of embedded URLs and the 'download button' heuristic further support the conclusion that this document is intended to trick users into downloading malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://adbuilder.at/ckfinder/userfiles/files/44985715111.pdf In PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/ca39822c19ae4bdd9809f92c987b80ff/5081593107.pdfIn PDF document text
    • http://ashioke.com/images/library/File/2702631289.pdfIn PDF document text
    • https://alariel.be/userfiles/file/jomituzura.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160fce41cd00a6---1184532033.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609bdfe784b72---voradawaxudemip.pdfIn PDF document text
    • http://kliknetezde.cz/admin/obrazky/file/gofofodajej.pdfIn PDF document text
    • http://polletnv.be/uploads/files/negamata.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/d4f6f9d6c7ce2a97f826e04d1ff0f85e/26879217940.pdfIn PDF document text
    • https://www.tamilsaga.com/ckfinder/userfiles/files/86678358920.pdfIn PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160806769aa5fe---36176547965.pdfIn PDF document text
    • https://www.bosingels.nl/ckfinder/userfiles/files/35839828912.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/sewosamefugejanatol.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/368b66d5837da9b51b4ba38abfc20a6c/jesetidugulakobedazazufu.pdfIn PDF document text
    • https://onlinendttraining.net/files/latojutivilamuso.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/96321793061.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16073f220d2909---33493358479.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/koderonubuvetofaxiko.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/48c1f05jtmdc6mn5fadtas5t35/fixaripovojowugofegideb.pdfIn PDF document text
    • http://www.halpellet.hu/userfiles/files/47951427129.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/g8b1nnad0jucjnb5he8dc3uf7l/79224485674.pdfIn PDF document text
    • http://www.alexgis.com/siteuploads/editorimg/file/nitipagopabironobumege.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/1rvdtl92rl9h3kgemlt04cfue2/96683421900.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160972bf108025---329756434.pdfIn PDF document text
    • http://wsmr.us/userfiles/file/43044462605.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=electrical+engineering+books+free+downloadPDF 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_off0000db74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB74 17580 bytes
SHA-256: 9c607b16d7154adc1e24c26cce99836a9f7f305df663bfae4d0fda072987e614
font_01_sfnt_off000108b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B5 10952 bytes
SHA-256: d49acfcd56da4125aad75c0f29f805c375d780506e7a19ef965cda3716c80bc1
font_02_sfnt_off00012211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12211 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1