Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e273c0b28a1797c…

MALICIOUS

PDF

78.2 KB Created: 2021-09-15 16:55:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 55646cec7b19a1b9ee3455bda9c18d0c SHA-1: 5636ec0248ed67aad829f607b90753ec8a5fc86c SHA-256: 8e273c0b28a1797c8b5193c763d0326d6a5ca2d715bda05d67c53b48ca0346ed
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 acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://nomylo.ru/uplcv?utm_term=offline+youtube+app+download PDF link annotation
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140eb2c0e4e1---lokibirojijewapave.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/89705246507.pdfIn PDF document text
    • http://ruizhishengwu.com/uploadfiles/file/032306157626.pdfIn PDF document text
    • https://ecosolar-energy.com/piceditor/file/74597248870.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/zapufabidepen.pdfIn PDF document text
    • http://studiomuraca.eu/userfiles/files/laxafivofugodowugepexarag.pdfIn PDF document text
    • http://gysanya.com/upload/file/210908180719370786eou6etur1jvy.pdfIn PDF document text
    • http://wgadget.com/file_media/file_image/file/favawivadigadepudexajuk.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/2021913241338693.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/65120414519.pdfIn PDF document text
    • https://jetaime-shop.com/files/pogewokubuwimuwi.pdfIn PDF document text
    • https://smilaxlabs.com/userfiles/files/vakub.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/loxogipawililakofunureno.pdfIn PDF document text
    • http://autowassenindex.nl/images/uploads/79395236066.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/62fbf42236f6f9c72f1b42674d4bac96/59913880625.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/19749588607.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/16138278d3faf5---xawibutazos.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16134926a2c57d---76341762238.pdfIn PDF document text
    • https://jecoexports.com/ckfinder/userfiles/files/ninefuxum.pdfIn PDF document text
    • https://shibbirs.com/media/files/kigawojibirazabevuvexadez.pdfIn PDF document text
    • http://manegedebuitenwijck.nl/uploads/file/82664948932.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/6eafa8fcff55ec49189df4b15c6e9cc5/xemafuwisatexekabedamub.pdfIn PDF document text
    • https://lederstuhlshop.de/ckfinder/userfiles/files/lojugegodataxuru.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/161359dc5b0146---35783087860.pdfIn PDF document text
    • http://jamxmpharmatech.com/upload/files/pufolorefapebunubapipobik.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_off0000cd0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD0D 17708 bytes
SHA-256: 9200bfa5a4ce2225b8bcec792b7cae86ed4bbb65a0d47726a89aadab3d96ba2d
font_01_sfnt_off0000fa4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA4A 10688 bytes
SHA-256: 5f0ace77e21424c4f3c086a31ba746a7a08d72ec94c3fe92c28e09142c8e7caf
font_02_sfnt_off000112bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1