Malicious PDF — malware analysis report

Static analysis result for SHA-256 a26576d73fac09c8…

MALICIOUS

PDF

81.1 KB Created: 2021-08-10 20:44:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 477d11b609faf1e9054b0812dbc3a30e SHA-1: b26d0e3ea7f5d50af260e18544be48d0189ec6e6 SHA-256: a26576d73fac09c845301418e75808f940261622bd8e72636786f5fb1708eb26
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, presenting numerous URLs that likely lead to phishing pages or malware downloads. The presence of compromised CMS upload links and disposable hosting further supports its role in distributing malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://valstybestarnyba.com/upckfinder/files/35903829295.pdf In PDF document text
    • http://nextgt.eu/uploads/file/mubipapanodimoxeloxole.pdfIn PDF document text
    • https://superpart.com/files/5259160905.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160f12d9098ede---33955061406.pdfIn PDF document text
    • https://nepalonetours.com/userfiles/files/kuwidiz.pdfIn PDF document text
    • http://pokorny-podlahy.cz/UserFiles/File/nuxow.pdfIn PDF document text
    • https://bazab.ru/ckfinder/userfiles/files/52249567902.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/a5bah85p8kjo69hvddi9rnbk5r/pasedomusi.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/480a5af017b395ab962b7e1eb0f7553c/71365740611.pdfIn PDF document text
    • https://pmcp-avac.com/files/upload-ckfinder/files/45247119137.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/21788664265.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bce88d8783c---kanimafenadesog.pdfIn PDF document text
    • http://npi-management.com/ressource/site-image/files/xekebifevinevilamedutoful.pdfIn PDF document text
    • https://ngoctraithaibinhduong.com/uploads/news_file/tadewizotevuvuvasivowev.pdfIn PDF document text
    • https://0924055971.com/uploads//files/202108041116245858.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160fd43e893619---fagitexinox.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/16070f9e1822ea---23474880403.pdfIn PDF document text
    • http://lab4050.com/upload/editor/file/kuwipokuderinupa.pdfIn PDF document text
    • https://biodent.ro/m4fm_files/m4news/ck-uploads-files/3644901365.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/60bf1edfc906d8827a2afe5f8ded4d38/3362383137.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1cb533702d---silisa.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1610e0f2f36358---bamar.pdfIn PDF document text
    • https://securitydm.com/slicice/file/lukawesilesije.pdfIn PDF document text
    • https://almondzwealth.com/administrator/imagetemp/file/jipaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=exerc%C3%ADcios+sobre+adv%C3%A9rbios+7o+ano+com+gabaritoPDF 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_off0000d24f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD24F 19224 bytes
SHA-256: 5cc55b481636e6422f72f6fe8406c15d7ac8e8f19f0351cfbee2045347ca57bf
font_01_sfnt_off00010133.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10133 11224 bytes
SHA-256: 306fbdbba63c4d71eadb81b9fe9f0bc40944b600707bef1849175743e3780524
font_02_sfnt_off00011b16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B16 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1