Malicious PDF — malware analysis report

Static analysis result for SHA-256 41b0d63b78b420f9…

MALICIOUS

PDF

96.4 KB Created: 2021-08-19 20:43:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f6544e05a406d5fe5d34cf177925bf26 SHA-1: 39cd9648aa98e402814a16cfe08db80f99586132 SHA-256: 41b0d63b78b420f9fa3b283c38aa4fbf2995491b4be662fffb3fca2b72793ee8
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. It contains numerous URLs, many of which point to compromised CMS upload directories, suggesting it's part of a link farm designed to host or redirect to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. While no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a phishing or malware distribution lure, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f991dcd3b50---70865348595.pdf
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1606ecbb075eac---vezojokivirokutanozer.pdf
    • https://binarbaidservices.com/public_html/userfiles/file/6307323075.pdf
    • http://mp-hd.de/data/aktualnosci_imgs/file/78272673661.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/4k3vgoh3tk36pp40qb972ea795/gikezojobi.pdf
    • http://ajmason.com/admin/ckfinder/userfiles/files/43045206277.pdf
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607d97909d24e---70167552104.pdf
    • https://bywuf.org/upload/editor/files/jebimavavazupu.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611a68e955a57---tiweviw.pdf
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160917eb941d22---45471596697.pdf
    • http://anhbanglaw.com/userfiles/file/58735561574.pdf
    • http://smartvoicecom.com/userfiles/suvizemarowelevun.pdf
    • https://unifor975.ca/userfiles/file/lekokaluwutidamanu.pdf
    • http://www.asslar.de/downloads/23836809207.pdf
    • http://zoldjogsi.hu/uploads/files/606662933.pdf
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/jqmkorjgumoft56p83jllsno91/37338662415.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/c8fm4hma1obuvk62vjd5jb0oau/58440906129.pdf
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/6263fd4de13f7ad5905ab4becf7a5e03/xejumetufen.pdf
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202104301616079595.pdf
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1074320052---lazax.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/u320rt8nc64lr03a11d62po27p/xapokimonijibiditut.pdf
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fc0b39d3e66---visatiruzufabigoxulav.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a06d3852c8---wibimaladufu.pdf
    • http://market-oborudovanie.ru/upload/file/41858311374.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a97b65e130---nusilasakunumuk.pdf
    • https://irantruck.ir/data/file/vafusiwimokuduwo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+configure+extender+tp+link
    • 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_off000115ee.bin
4e124673b665eafe0bfddb4383240de3c69e7023f5a6e08aa9aba9a65c843d46
pdf-font-stream PDF embedded font (sfnt) at offset 0x115EE 10836 bytes
font_01_sfnt_off00012edb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EDB 16792 bytes
font_02_sfnt_off000146ed.bin
00040002717ddb81c4ec87da6f78ecb935be8a3d778a8023deeb3c45ca19ab48
pdf-font-stream PDF embedded font (sfnt) at offset 0x146ED 17020 bytes