Malicious PDF — malware analysis report

Static analysis result for SHA-256 f55c5524314ce84f…

MALICIOUS

PDF

79.5 KB Created: 2021-09-05 14:59:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: fc763738da70e16f6fe2a57f68c47af5 SHA-1: a1649600b7c4ccbc3f32800acf036fd4ee84e774 SHA-256: f55c5524314ce84fcc5ecfe08a97d265f6d58f6f5591adbc417f316c678325bd
156 Risk Score

Malware Insights

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

The file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The PDF contains a link farm pointing to multiple domains, many of which are hosted on compromised WordPress sites or disposable hosting, suggesting an attempt to distribute malicious content or conduct phishing. The presence of numerous external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://lescourailleurs.com/upload/editor/file/37867743614.pdf In PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/3mq7afh2ha1nn0g3ao7eol2kp8/77365338697.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/ef8ed4fa3214582d0ff342b42b83619e/76674390736.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aa7a3e637ee---werujabuxopurefuguxet.pdfIn PDF document text
    • http://thueotodn.com/uploads/image/files/39873117196.pdfIn PDF document text
    • http://desagresbrts.com/clients/34568/File/subilewori.pdfIn PDF document text
    • https://planet-for-events.de/userfiles/file/45061193658.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/59b52c246adf5fe5799cc66876fb4517/bikademalali.pdfIn PDF document text
    • http://vce34.ru/attachments/file/rewasedanavuneximoze.pdfIn PDF document text
    • http://surausa.com/uploads/files/36340020970.pdfIn PDF document text
    • http://kutyasturak.hu/images/files/23420862401.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160808fb18b090---jujeberazojob.pdfIn PDF document text
    • http://biosite.ru/images/news/file/dinoguwipijub.pdfIn PDF document text
    • https://transmar.biz/ckfinder/userfiles/files/vamujibenax.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160afe5ae1a642---14297391619.pdfIn PDF document text
    • https://filetorme.com/upload/files/vopiwizumaf.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/5993bac7ed0bd034fabcc08e65065a85/valobinofizi.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/50ni38qi7kuqgumtehjpglg3do/44931652156.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/flauhj48lf2dj5itaa90bofsuq/37968209750.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/d4222b43fad5a37b2cd272fad159021c/88554129907.pdfIn PDF document text
    • https://adtw1.com/ckfinder/userfiles/files/buwukiv.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/98af5a9b836afdab9c11fcb636d62881/7960019789.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///mopuxavipivexukoz.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609887ff581c7---bogubopiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=free+printable+language+arts+worksheets+grade+3PDF 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_off0000d37e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD37E 16516 bytes
SHA-256: 8b10960dbcacdbb7bc95882422151e80ce6acc896b9c780f0c3535cba8ef7e14
font_01_sfnt_off0000fe67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE67 11236 bytes
SHA-256: c3cba0cfee4f9d066bc8a378c37271d2db81695a41ce6c9e941edc963222630c
font_02_sfnt_off0001184c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1184C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1