Malicious PDF — malware analysis report

Static analysis result for SHA-256 a86450ba1b06df1d…

MALICIOUS

PDF

82.4 KB Created: 2021-09-15 08:58:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8561989781ea568ef207e5a36f3af2b4 SHA-1: e8b2579fc15379b26dbc0ad38f111e27af272163 SHA-256: a86450ba1b06df1d89afd147c9e2c48f31d4b434843564669bbed4b3c536d881
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. The embedded URLs and the overall structure suggest an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://queure.ru/uplcv?utm_term=garry+kasparov+my+great+predecessors+pdf PDF link annotation
    • http://isvpro.com/custom/files/77232194997.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/21059328631.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1614154c28f5c0---10281831579.pdfIn PDF document text
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/40324505301.pdfIn PDF document text
    • http://huynhgiabaohotel.com/uploads/FCK/file/bufikerenun.pdfIn PDF document text
    • http://ets-sptk.ru/pic/file/26150133775.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/23972099628.pdfIn PDF document text
    • http://alptw.com/images/files/69681570599.pdfIn PDF document text
    • http://kahasat.cz/data/file/81922377699.pdfIn PDF document text
    • http://gsmontaggi.it/userfiles/files/fidaguzebobibofexebakoke.pdfIn PDF document text
    • https://bunian-co.com/other_files/File/zoparapofigirugu.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16134ee37eea92---pixavegu.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16141516e728e8---buguverasofub.pdfIn PDF document text
    • https://biodez.lt/i/File/81294852452.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/gh57je0rv6gekmnv70srbhq0js/torolitut.pdfIn PDF document text
    • https://ausztriasi.spawellness.hu/upload/hirlevel/files/zafulejoxi.pdfIn PDF document text
    • http://vdavloeren.be/userfiles/files/43741745279.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/zexilijarokoxuperijag.pdfIn PDF document text
    • http://twsl.mingann.info/upload/ckfinder_temp/files/20210913074852.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/lilodowagavidapewe.pdfIn PDF document text
    • http://cngwalk.com/fckeditor/userfiles/image/60353860347.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/4bbf0485aeeda09db8f4314b1bc3c983/genosifagaxesotu.pdfIn PDF document text
    • https://myarchitect.es/ckfinder/userfiles/files/31238846209.pdfIn PDF document text
    • 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_off0000ddc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC8 17312 bytes
SHA-256: 92719e122ba30d33fd7ce1bd1060bd186362ed4af8714428c5ba32074dc8873b
font_01_sfnt_off00010a02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A02 11032 bytes
SHA-256: ac2f5b69d43a5b2cc084e56d672d256ff56a150ad17e26f08c0e1018d7c8a37a
font_02_sfnt_off000123a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1