Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca7ea95fee7e8f07…

MALICIOUS

PDF

81.9 KB Created: 2021-09-17 04:37:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c2c527922e9a6278ca769c5c1202df7b SHA-1: 156c267938df1c259e4a79c8a1b22cea3335ea7c SHA-256: ca7ea95fee7e8f07401eb348a1bf17c2a4965a17beea6bdfc70b810a948ed3a3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded links pointing to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection further indicate malicious intent, likely to distribute further malware or phishing content through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://ketchas.ru/uplcv?utm_term=aplicaciones+para+abrir+documentos+word+en+android PDF link annotation
    • http://tinhdaurosa.com/Images_upload/files/werelitegapixopulaluzeg.pdfIn PDF document text
    • https://www.mnogotrop.com/ckfinder/userfiles/files/sipaledofoxuxupigi.pdfIn PDF document text
    • http://esistore.lu/userfiles/file/wemogejoma.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/627075996.pdfIn PDF document text
    • https://ngusacdon.com/upload/files/9323703097.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/fagisusunuveruwom.pdfIn PDF document text
    • http://flamefitnessstudio.com/cewit/images/file/redejunulosime.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137bb6442408---wogedubifebanolunagozol.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/s81q9l923ovoaag23ehduqqlh4/pubenuduxix.pdfIn PDF document text
    • https://ciela13.leaddeehub.com/userfiles/files/19879044532.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e231117cc5---64632148691.pdfIn PDF document text
    • http://autoklej.pl/app/webroot/media/files/lasanotisevokasusetiv.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/2s3epsvu8shgki5rn0rou5he51/64851066148.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210911053051009.pdfIn PDF document text
    • http://datavincity.com/uploads/ckfinder/files/viwamex.pdfIn PDF document text
    • http://zjleiou.com/images/upload/File/lagogefexufakel.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/d84c41c3be7f675d0eafd34e40ef085f/51153520822.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/toberejan.pdfIn PDF document text
    • https://htlexpress.com/ckfinder/userfiles/files/pigolazofimime.pdfIn PDF document text
    • http://mebelhotel.ru/userfiles/files/45756516496.pdfIn PDF document text
    • http://whuntex.ru/userfiles/file/67231797614.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_off0000d5c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C1 19248 bytes
SHA-256: e5c8bc0dc1ecd538c3e8da3a118522febe525b3326a5ddbf75d7413d5acd9120
font_01_sfnt_off000106cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ee4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EE4 10980 bytes
SHA-256: 559b787fcfb6ff1499508dd042946c7652a5f7f5da5954f23e9d28f460b4b37b