Malicious PDF — malware analysis report

Static analysis result for SHA-256 df1940d79a348b7c…

MALICIOUS

PDF

79.8 KB Created: 2021-07-19 01:30:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: eb0f63b86795a3f44fc3964d0ace1c29 SHA-1: eb74fb8f6f06245307b7e04483f1d91ff00f217d SHA-256: df1940d79a348b7c3bb4e9eec6ad9b797303642fe61a65fc52d51ba32b027dcb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link farm hosted on multiple compromised WordPress sites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the nature of link farms in PDFs often involves JavaScript to facilitate redirection, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/2fru83orolhs7lclp2o7nf7jmo/zepemupowo.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a536ae8c1b5---44384226635.pdf
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/hqjfo719lgupkmlncmqqs0viud/83525122699.pdf
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/6tkkp7cn7eceai4d2ml9j54p85/punoseruwixut.pdf
    • http://dynamic1984.com/user_file/file/46518118841.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/047d793eb6a0dd14fa0b347f3fb988d2/rumitolotagelepu.pdf
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/bc5bc9ae34a4731bc6d347aa7a85847b/womuzi.pdf
    • https://honda-otolongan.com/upload/files/kizunemoj.pdf
    • http://wallacewilliamsfamilyreunion.net/clients/6/66/662ca4338cd1fa41fa93b88222973dc6/File/kotokajaraku.pdf
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/2597268923.pdf
    • http://bagliodeimille.it/userfiles/files/gazolupuru.pdf
    • http://kirsanov-maslo.ru/uploads/suvejivamejapiluz.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/0bafa7a24303eea2ff04229e90dc3045/nutoxijin.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e32583927f---32356998929.pdf
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a30358bd4b1---38205783862.pdf
    • https://ilexgold.com/app/webroot/files/userfiles/files/78315202159.pdf
    • https://alakharia.com/public_html/userfiles/file/zidogomap.pdf
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160829b885d642---wabakazakikaxaron.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/7822e9605abb87634257c18763bac119/29781317947.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afac6649209---wukafukorixes.pdf
    • http://jcon-aps.dk/userfiles/file/40168229149.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=can+i+convert+a+tiff+file+to+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d677.bin
08a2bd05bc6b46a88c9d4392de0d1c519a4ebeb755705ecaa5c9a90973ac4282
pdf-font-stream PDF embedded font (sfnt) at offset 0xD677 10544 bytes
font_01_sfnt_off0000eea1.bin
5f19a5133ce1473efb5aa4e8a1f48bf0a39e2fcf2e658affc596c8709360a297
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA1 16984 bytes
font_02_sfnt_off00011acf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11ACF 16792 bytes