Malicious PDF — malware analysis report

Static analysis result for SHA-256 20408096bf64d4ea…

MALICIOUS

PDF

74.4 KB Created: 2021-06-25 21:14:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 9a471e28e951b2b91159269187974fd6 SHA-1: 3dd9441239ca0b483bd583b28ea6132662e18cc3 SHA-256: 20408096bf64d4eadea352e72ceb6ae23538e845c86be936c193678f99464c7f
96 Risk Score

Malware Insights

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

The PDF document contains a large number of embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicates maliciousness, and the structure suggests a link farm designed to redirect users to potentially harmful content. No scripts were extracted, but the primary attack pattern involves luring users through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://chcial.ru/uplcv?utm_term=i+am+always+alone+quotes PDF link annotation
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3973d22542---vizimoverizetavisowede.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b751149bb5f---89727556567.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16081b3cfa438d---11527660484.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/a916a839e79153b02d411574fd28ca8f/tobugibo.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/vunigepomapidanus.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608569dbd5bcc---67768290801.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/374d9a07442af0087052313da600009c/86047657379.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a78cc415513---22961885335.pdfIn PDF document text
    • http://hyperasp.net/userfiles/file/8467324046.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8870005963---14670475844.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160701f9da93d6---mumositujomo.pdfIn PDF document text
    • http://vinhthuan.com/upload/files/3280969140.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/do411djf8ns3jhj5tah6nhgss3/49756747784.pdfIn PDF document text
    • https://euroroma-bg.org/files/file/fisawevu.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f5f193a594---kipipezipesigijew.pdfIn PDF document text
    • http://gruaszarate.com/ckfinder/userfiles/files/xusitu.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/91777364789.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160717464915c8---83152545757.pdfIn PDF document text
    • http://winfielddeli.com/ckfinder/userfiles/files/niguro.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/fosatuxajoxugiwexi.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/4e651168c619d34baa351037bdb4c16e/fozasopafotipewevavosuv.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/eb79a1b16650243caa7ec028a15bc748/35197794451.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607356c17513f---nutenobanejis.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a256de75129---9521080520.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_off0000c131.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC131 10472 bytes
SHA-256: ce24363e782a7faf557d3be8264aacbfcf05da578d6cc56940ba2eddf1347798
font_01_sfnt_off0000d91b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f12d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF12D 16892 bytes
SHA-256: 807aaaa843703c865d7e993afe45d4b3a19c3c339047ba19e34ad2c645aabafa