Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d374c28c4a0eb8b…

MALICIOUS

PDF

81.7 KB Created: 2021-09-07 00:27:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c4f0226588e3da86c34602fde120e398 SHA-1: 4cc9bdbe8d9c4cc9fa0063d662e8066e354d4db7 SHA-256: 1d374c28c4a0eb8bef8837f3878aa5377d38cd57184700b9139dd4c467d377a7
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or are part of link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and compromised CMS upload links suggests a tactic to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • 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
  • 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://crysiq.ru/uplcv?utm_term=4th+and+5th+grade+language+arts+worksheets PDF link annotation
    • https://benqmusicworkshop.com/fupload/file/2211767251.pdfIn PDF document text
    • http://dgjst.com/upfile/file/35424276527.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/753b4d0680f34899f35e809877fdf336/66616072898.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16096f9088b1f6---daxifibufir.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd05440298---60759506347.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/67342547035.pdfIn PDF document text
    • http://daiichibus.vn/uploads/news_file/ginajan.pdfIn PDF document text
    • http://resortvillairene.it/userfiles/files/jubeg.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/4e557e5c6deda980acd9794d342381e7/rofuzalifotedavusokufaze.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/phelkv248jsh8pre6vaj0mt7m6/dewepufazejaji.pdfIn PDF document text
    • http://aloeverajuice.cz/files/file/62021716757.pdfIn PDF document text
    • http://hanasushi6.com/uploads/files/gojobevinoresij.pdfIn PDF document text
    • http://wittlich-luexem.de/userfiles/file/vigeruxad.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/v8kafu4c82kmlkekp2vvvtblqq/74135644101.pdfIn PDF document text
    • http://guides2alpes.fr/uploads/file/lelirixapoziwikowoxuvu.pdfIn PDF document text
    • https://okvino.it/file/14228867369.pdfIn PDF document text
    • http://hyundaiokla.com/uploads/files/27164755026.pdfIn PDF document text
    • http://home-hj.com/up_photo/file/toxoxer.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be8e8096906---24922212561.pdfIn PDF document text
    • http://wedding-ideas.ru/ckfinder/userfiles/files/41275930622.pdfIn PDF document text
    • https://tl-systems.hu/files/files/52314943755.pdfIn PDF document text
    • http://unitec-egypt.net/userfiles/file/50155393095.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_off0000dc09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC09 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f41b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF41B 17092 bytes
SHA-256: eb7f934433ee8053d74a7b6687f98a3f00191461bdecb452e00167dd5b3e18fe
font_02_sfnt_off0001203a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1203A 10828 bytes
SHA-256: 4a1439676df650ff8b10fecfe3da509dd76f250172fcda36c43a128ffced134f