Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4a55fb8704a8d88…

MALICIOUS

PDF

76.6 KB Created: 2021-06-30 17:22:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 035c4ad5177474db373c87dae1599090 SHA-1: 09203da6edc3cfac3b56a4ec491c0de2ff2a3301 SHA-256: b4a55fb8704a8d8829a0d136b3b210056cdc7e316236ba1e1b8f408d86edc4fd
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document that contains numerous links to external PDFs hosted on compromised WordPress sites and disposable domains. The heuristic PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM indicate that these links are designed to lead users to malicious content, likely for phishing or malware distribution. The ClamAV detection further confirms its malicious nature, classifying it as Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://responsible-tourism-alliance.com/content_file/files/98626447262.pdf
    • http://seamcc.com/UserFiles/files/bopadoparik.pdf
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/8eg08587426q8r37gguo4spd43/gupokovepijifajoro.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a71b95aa19---pizuvaxudoxewosi.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0bd427acb2---9081533384.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086f460dc29c---72414101214.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076194854bda---kanufis.pdf
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/fojaviloravefebuzizuxuve.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3847f7d327---purifoloraxolaniderivir.pdf
    • http://kimwendelldesign.com/ckfinder/userfiles/files/fimagukipede.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607ccf917c75b---wulagozokewaz.pdf
    • http://bollywoodsalonskokie.com/admin/images/file/30715133309.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/dd3db3416becea06dfe49a2874963266/mokezof.pdf
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/3274810e916412652d9378272ca012a8/83743398361.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a73e973db46---25580405856.pdf
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/73589017087.pdf
    • http://thedewakohchang.com/image/upload/File/ipinokefa.pdf
    • https://stalbeckers.nl/userfiles/image/file/30797113977.pdf
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/3cff76d546ce6733411c06c9b1e80c72/2546163937.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2a96f17a1---riritidowotaw.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b53d159b68b---12471027131.pdf
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/8555bc71fb341defcde51535ec56f430/zanutinisibevudefusuboxas.pdf
    • http://reicar.dk/userfiles/file/25212527452.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/jlmh9qkogq5i636i0vcinm1mq0/17342798428.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=the+conjuring+1+full+movie+watch+online
    • 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_off0000c87d.bin
58dced9da822b2c65348fecc774c76fa1d688ec50ba3bd8c416028ad9ecd2907
pdf-font-stream PDF embedded font (sfnt) at offset 0xC87D 16620 bytes
font_01_sfnt_off0000f3a6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3A6 16792 bytes
font_02_sfnt_off00010bbd.bin
42418b055fa0380c07ed8eb1ef227a7d2c4717273cb561843fd757f094a1aa32
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BBD 11012 bytes