Malicious PDF — malware analysis report

Static analysis result for SHA-256 52122c103f3b5c02…

MALICIOUS

PDF

87.6 KB Created: 2021-07-01 20:44:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c3e0412907cdf95ebce0788a0edb3ba8 SHA-1: 04100543b1132f8e21fc4236a48c7c97e2f24bf3 SHA-256: 52122c103f3b5c0221560fe8fa0fa6588a42c3a17f507c5bb04a03fbf73052de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and the presence of external URIs indicate it's likely used as a lure to lead victims to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1609ae8db9755d---36481444798.pdf
    • http://droprint.my/home/ququ4923/public_html/userfiles/file/remomu.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/81162bf608acc02b75521b7a5c751651/28148099496.pdf
    • https://kaptenhoki.net/contents//files/fokusixulexukafaxubako.pdf
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc13f8dede---sefuvasefixotam.pdf
    • http://studiodabo.eu/userfiles/files/jizavodemoduw.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c06d8c02c53---71030776342.pdf
    • http://didopack.com/files/1396772549.pdf
    • https://bititechnika.com/uploads/file/90060163384.pdf
    • https://mertlakustika.cz/images/pages/file/45807548701.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/ci95bacad4cdts104uimtorn72/pitinut.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160dbcbc8cc527---30420701300.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/41d392e76e3f13143c6e1ce49daaf131/wifelufivivepabon.pdf
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/89383785576.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/ec414c11dee5b182cf0b50224efcf38f/jizomiwusakozuzinepuxizar.pdf
    • https://consultingexpert.eu/fckeditor/userfiles/file/mupirusile.pdf
    • https://tomas-music.com/contents//files/gofetexukutitoxe.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ad008cec12c---89273244561.pdf
    • http://3bbb.fr/ckeditor/upload/files/reviwonifabugizirenon.pdf
    • http://accessprecision.com/userfiles/file/95382950044.pdf
    • http://caratow.eu/userfiles/file/binozaxegobima.pdf
    • http://am-assets.com/aom/magnolia/userfiles/file/41378076809.pdf
    • http://come2menorca.com/images/file/tupalisolepemi.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/c1a1b365725b9a9017c616fcb8422e05/nenepemuvo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=inmates+currently+incarcerated
    • 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_off0000f48a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF48A 16792 bytes
font_01_sfnt_off00010ca1.bin
e5644acfa465941e595f012d55a25b4da21ab0300f4859dc1652cdc2c18a0e2c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA1 10576 bytes
font_02_sfnt_off000124b5.bin
5ccde12b819687344b7b7dba504decba9c9b48de7300ae5ff20b9c179adfc7de
pdf-font-stream PDF embedded font (sfnt) at offset 0x124B5 16968 bytes