Malicious PDF — malware analysis report

Static analysis result for SHA-256 7373948ae7e8ef82…

MALICIOUS

PDF

100.8 KB Created: 2021-07-07 18:33:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 8a4f94c8bd86f0581a96ef6c1e2fad03 SHA-1: dc701da1caf58db7b0e1501cb95dc49e36ac1956 SHA-256: 7373948ae7e8ef82044bcad40b65c2afad2a1eaa9bf13353e82a614c46b2b934
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous URLs hosted on compromised WordPress sites, likely intended to distribute further malicious content. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF is part of a link farm designed to obscure the true destination of malicious downloads. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

Heuristics 5

  • 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://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/358d33592fbc2aac7e7330936b1aeaa3/91058968572.pdf In PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/2c037748ee482528837799879c005223/82127765914.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/c307f3f77e646dadc4df9ad10e53ef85/96107804016.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/17mi1pkfs0otmue2k6iiku7p9o/48432514026.pdfIn PDF document text
    • https://digireg.dk/upload/46155965700.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070e53e4a31e---jepexoreginudowi.pdfIn PDF document text
    • http://location-venise.com/italie_documents/files/35418907544.pdfIn PDF document text
    • http://sushimura1.com/uploads/files/54474884800.pdfIn PDF document text
    • http://masan315.net/board/imagefile/file/fuxejivituzuza.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609682e72f242---88181431329.pdfIn PDF document text
    • http://ngocvietbungalow.com/upload/files/46646112914.pdfIn PDF document text
    • http://music-saikung.com/ckfinder/userfiles/files/mizenajomidemugaxomuba.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/dc1d320733f2bdae99dabc7e8cd7829d/jibiziniwa.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/f28b449b104e866121127f15d574c43f/51211225397.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16071da3a94810---fomupixozikatumibep.pdfIn PDF document text
    • http://hoangle.vn/uploads/userfiles/file/25622750347.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/1cf88bdfbd0996991663ca8741362ca6/mimolat.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/d44f19ca0b8c3a197399fea1f98c45a1/1614919709.pdfIn PDF document text
    • https://thai-airpark.com/ckfinder/userfiles/files/rozonoxilosefusikulix.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160928c3d7208a---gememurexomojav.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/46384212306.pdfIn PDF document text
    • https://anup.bo/images/files/makodozadosuvetozelaro.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-6-20/20210620170037657753.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/9b65fbe140caeb0627317f80f295580d/63372655771.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=pdf+free+download+fifty+shades+of+greyPDF 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_off00012228.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12228 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013a3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A3A 19660 bytes
SHA-256: 4227dc9bc0a6675f44134e3b2fa8b81aafa78b1dd003837e35a545ac57554fbc
font_02_sfnt_off00016d30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D30 10836 bytes
SHA-256: c50c1f6903927b6838c200acd8d7e99b43a5ea3b5046d2dbb71bd656a356e28d