Malicious PDF — malware analysis report

Static analysis result for SHA-256 f52b6e1c736aca1a…

MALICIOUS

PDF

86.0 KB Created: 2021-06-25 17:43:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: e6d5e004503a7aa6c0c5ddd1914fa4c2 SHA-1: b1a3468d9c76d34e3edc3e3c9aa61d9265328d23 SHA-256: f52b6e1c736aca1aa1c5921dea20447dcfe7865fde245c606bb198c434905ebb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The file contains numerous links pointing to compromised WordPress upload directories, suggesting it is part of a link farm designed to host malicious content or redirect users to phishing sites. The presence of embedded URLs and the nature of the heuristics indicate a likely attempt to lure users to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cbf38e5a7e7---xetejesotolubaviromale.pdf In PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608b9d30786ab---femapokosumamirowugu.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16082b60a63680---75162071545.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/acf9c504f433c4d336ec7fda6e211fb1/bafadawefojitidire.pdfIn PDF document text
    • http://planbmedia.hufiles/mapanudolamizusefu.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608920c77032a---6540289399.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609681bc8f89c---sevoru.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/dixudumesilofuludapufusal.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/kiruzotofawepugalatujo.pdfIn PDF document text
    • https://sportsht.com/userfiles/file/pururojulipofasexu.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608bedf29ba24---76177450107.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/cda5eb11ccf1b7580c2e53cec08a461d/94537237253.pdfIn PDF document text
    • https://nguyenthelong.net/userfiles/files/nukaziriguda.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d30bc7362---59274773306.pdfIn PDF document text
    • http://caffepontoni.com/uploads/file/xixinolegalarana.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/b431e0f7d7a0373596ded16392fb7885/21816230074.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094c7543b541---gowilifu.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/4269vgud5u2h0t2rmvd31gp297/89729342452.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/p8hnv0v20daukeruvuv74puuga/kujomimesixelerulidede.pdfIn PDF document text
    • http://terralindahigh1981.com/clients/866868/File/nupujixilovanikoxebi.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b4f351ebf8b---76635895419.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/73cc98cf828e0cdb1ae7bd7f5d79fe70/xalenuxoxadirakeribo.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d59f00477a1---neronemuvem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=mohave+county+property+tax+searchPDF 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_off0000edb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB9 10708 bytes
SHA-256: 244f8f9597083ed8ac834d9597bd5c9734c3729f7dd7dc19755faaddfc6f6ad2
font_01_sfnt_off0001065c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1065C 16936 bytes
SHA-256: c35665a25c07b092e51b2099c36363eb042043e02967e42a11d4fdab6762e4c4
font_02_sfnt_off0001327f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1327F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1