Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae7f573b1354f6bd…

MALICIOUS

PDF

80.3 KB Created: 2021-09-18 19:00:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 32eaeb7b1c58661e6ee9f4dad07f5f82 SHA-1: 3a6d1beb5ff99cf7b0b6d921a532b106a0b87727 SHA-256: ae7f573b1354f6bdcd817f70f75d7e3c0ccfce8da8e093a451aeb3ff6d12bd67
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting. The embedded URLs suggest a pattern of redirecting users to other PDF documents, likely for SEO spam or phishing purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://davidfoleyinc.com/userfiles/file/kalawewidajod.pdf In PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/3e2a327a371c046b7eff54923ec9acc0/pewatajexufusixawafe.pdfIn PDF document text
    • https://phuquiland.com/upload/files/xiwaluxirozizojegutedep.pdfIn PDF document text
    • https://harkakotony.hu/UserFiles/file/vifedog.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210904000033.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137addd2b847---zinuxosek.pdfIn PDF document text
    • http://www.ocptecnology.com/admin/uploaded/fck/file/98669854641.pdfIn PDF document text
    • https://mlspoland.co/files/file/67296288081.pdfIn PDF document text
    • http://guide-eq.com/userfiles/file/20210910070352_bzmnrz.pdfIn PDF document text
    • http://spc1991.com/ckfinder/userfiles/files/soditizevotatepobaxe.pdfIn PDF document text
    • http://redeyeldn.com/userfiles/file/tuxosu.pdfIn PDF document text
    • http://americansemitruckparts.com/d/files/kapila.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/78522058458.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/86144576176.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/pajosutaviwudesijejoleg.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210916_6B1E47762EE61781.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/sazedu.pdfIn PDF document text
    • http://a-b-i-s.net/layout/bilder/file/38642673490.pdfIn PDF document text
    • http://presssimayeshahr.ir/pic/file/lanumibakumepapezu.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd047619ac---limek.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/edb03376560fc0408bb47db2945bde8d/23285479989.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161391d4a44610---dopebakiradap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=post+polio+syndrome+doctorsPDF link annotation
    • 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_off0000d4c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ecd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD7 17892 bytes
SHA-256: 6e8c989fbf9b68468f2eaaa20ac9d6847c9a12e39cf8b2c4b5b663ad67fcf246
font_02_sfnt_off00011b31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B31 10628 bytes
SHA-256: 821e3641764b5507185ec3d0039b94888211a20465b78ec0aec3af98e6792caa