Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a9165e4bde704c3…

MALICIOUS

PDF

83.8 KB Created: 2021-06-29 19:16:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: ec29e22209425f3e8efc24dac4b9d4e9 SHA-1: fb5644772afd7b9ca8aa159e070cef626035f610 SHA-256: 3a9165e4bde704c3216cde03400cfa072c13b6694e1d39553b7f4ffa8128bf81
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and heuristics indicate this PDF is malicious, likely serving as a link farm to various compromised websites. The embedded URLs, such as https://medvor.ru/uplcv?utm_term=how+to+change+a+layout+in+powerpoint, are designed to redirect users to potentially harmful content. The document's structure and the presence of numerous external links suggest a phishing or malware distribution attempt, possibly leveraging a spearphishing attachment vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 5

  • 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://medvor.ru/uplcv?utm_term=how+to+change+a+layout+in+powerpoint PDF link annotation
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/zuzukuvarezumodifuxejin.pdfIn PDF document text
    • https://aviseco.ro/userfiles/file/figusoweronipugo.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/ne7lf74l12vk44n14cm1pgfp7a/36735102244.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16076f26b0d6b8---37600063586.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/32691739783.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/bd669123e6214216908c3409d51cf092/javifebatirikixu.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a018345b3f9---68928167979.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/1st75dtq8ut77fj3p5ob7jp7rn/62108952093.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160c850ce8881a---bixokokopivegufezav.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/1c04495c4a2d3fedbe7c7525cb9830c8/2380739414.pdfIn PDF document text
    • http://aimecostruzioni.it/userfiles/files/bujevafopogolugulak.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/8605eaecafda54e1b6fc81d76e801fc5/45134345822.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/65739087598.pdfIn PDF document text
    • http://planetamama.ru/files/file/14111520529.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fdc32e909d---fibupidaxavirujifabolipev.pdfIn PDF document text
    • http://locthanhwindow.com/img_duhoc/files/sowubumixafirisutitep.pdfIn PDF document text
    • http://kaowei.tw/image/files/20210601_032629.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608612c4c44ee---27293865235.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/84879883715.pdfIn PDF document text
    • http://portalpr-b2b.es/img/user///file/_0614974001624541464.pdfIn PDF document text
    • http://vo23.ru/upload/file/74765080245.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_off0000e53a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE53A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD4C 16964 bytes
SHA-256: 550efe1da59ed33b9b2d4238523948b28897de3278f732875600bc51227a3de8
font_02_sfnt_off0001295f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1295F 10776 bytes
SHA-256: 5474061839f5b64531c57d72f092b541797792bc2304b812649d76ccfbfe499b