Malicious PDF — malware analysis report

Static analysis result for SHA-256 f91091cfb04e1f82…

MALICIOUS

PDF

81.5 KB Created: 2021-06-29 17:56:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 046e9bce316b388f1da668a295a0be1c SHA-1: d9b03765dfbe5dfe542147aab1e61a6aecfa4981 SHA-256: f91091cfb04e1f82f214d737a8bbbf74d892421ca1dda9f475c9bf70a95cb6af
124 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan. Static analysis revealed it functions as a link farm, with numerous embedded URLs pointing to compromised CMS upload directories. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a pattern of using disposable hosting for these links, suggesting an attempt to obscure the true malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4208

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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
  • 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://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/550ff7e889020512ac50442e180668e2/wafugonilaki.pdf In PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087e22f292c3---80779106461.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/4a5a90295db154f233be5a8dc377fe5d/57920251973.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160ae26de858c7---lolukuduxixagijejel.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/30307306651.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/mubasimonuniriju.pdfIn PDF document text
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/699dd0b9108086de3f9cf624202ae435/63724372455.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/mopakuluwinexoweremo.pdfIn PDF document text
    • https://aiwatopup.com/ckfinder/userfiles/files/gewetejige.pdfIn PDF document text
    • https://activepymes.com/pub/file/29017672144.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5f12083f4a---28551330777.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/e7cb7fa2a6614aa5ad891454a146ba24/vunivakuril.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8de6046a3---56093119692.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a0978dd4091---mididonovu.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16071a1a402e8d---purifenilixeg.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ba76e60b4a---rikefibekis.pdfIn PDF document text
    • http://bukvoznaika.ru/ckfinder/userfiles/files/fanemazetixozimasotelufo.pdfIn PDF document text
    • http://engroupe.ca/aym_image/files/28458831820.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607edf488c592---bewivadakinifiji.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/67209668551.pdfIn PDF document text
    • http://agarimo.com/archivos/archivos/finijezijekurafigaba.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/85e15b6735e393f35dd432bd31459d01/94229305387.pdfIn PDF document text
    • https://renault-service.com/userfiles/76055909198.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/9a1ace0b9a9667c7eff602efcff81e1f/89600871561.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=dollar+puzzle+answerPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF427 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010c39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C39 17976 bytes
SHA-256: caabb2e34540921aa393dae86a8ee3ed889f4efa8b9e6f33bd595949ea2f29f0