Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d3dc40e70d4f848…

MALICIOUS

PDF

77.7 KB Created: 2021-09-03 21:18:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5c9da680a61134b62684944e018a077a SHA-1: 533cca65214aed4632da76a5a4273faa9e7e6c6a SHA-256: 1d3dc40e70d4f848ad8d105769ab972de5fe8a56dc2dedaceeb5ebecb97da703
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware hosting sites. Although no scripts were explicitly extracted, the PDF structure and URL analysis suggest it's designed to lure users into clicking links, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 http://medicapoland.pl/uploaded/file/75572812603.pdf In PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608c9dc6783c8---sepomog.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6d67511fd1---valurasodimunetuxopu.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/19m6sc332jff3tludhpm4c03l0/rebom.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ff894bb4eb2---63907033451.pdfIn PDF document text
    • http://www.bordadoindustrial.com/ckfinder/userfiles/files/fezomiberiwip.pdfIn PDF document text
    • http://wisdomtours.net/upload/file/70018189972.pdfIn PDF document text
    • http://slmj8.com/data/userfiles/files/sokalimomiladufi.pdfIn PDF document text
    • http://gowowdeli.com/uploads/files/digup.pdfIn PDF document text
    • http://muzeumostrowiec.pl/obrazy/file/sudikumeruwuv.pdfIn PDF document text
    • https://www.karelo.com/uploads/File/fuvevevefajifowozomi.pdfIn PDF document text
    • http://www.ciesol.com/ckfinder/userfiles/files/vunuxusomitafil.pdfIn PDF document text
    • https://bosgo.mn/uploads/files/gozunovukuse.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160932df76f6a5---27671953329.pdfIn PDF document text
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/5612722361.pdfIn PDF document text
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/36582419875.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16085318d31b79---52598964513.pdfIn PDF document text
    • http://aias.pnu.ac.th/ckfinder/userfiles/files/3899087216.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16130bb870f8be---29843658400.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611f32f04ef6a---selodoneme.pdfIn PDF document text
    • http://dailycan.com/userfiles/files/46612892135.pdfIn PDF document text
    • http://kibbkw.com/uploads/file/zamomidovepapo.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/dc43536776ee6eed48b0e21fa5ce0c43/patamaro.pdfIn PDF document text
    • http://deepakbatteries.com/uploads/file/vikazota.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/1528285526.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/14991434778.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=subtraction+on+number+line+worksheetPDF 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_off0000ca36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE248 17412 bytes
SHA-256: 772e5dc56a1c781f40ed37661797934b4486edf79287dc2f7c3c80cff077d8a7
font_02_sfnt_off00010f3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F3D 10988 bytes
SHA-256: d970e64a0709043bf2aa406939abfd162e1d9543e6546a1467f547077e9382aa