Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bca81158d36d578…

MALICIOUS

PDF

85.5 KB Created: 2021-09-01 00:49:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c8f42bf0d5a7b8baae368c464287c103 SHA-1: 7602393abc3a1698873ccbce4aa280b8e94165a3 SHA-256: 9bca81158d36d5789965847471b57b2cd34746008e4ff47739790f5d1cf49b5c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, with several pointing to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://irlanc.ru/uplcv?utm_term=days+without+sex+jokes PDF link annotation
    • http://aquamedia.cn/ckfinder/userfiles/files/mubexizated.pdfIn PDF document text
    • http://energosol.pl/images_cms/file/96882027563.pdfIn PDF document text
    • https://austarpharma.com/upload/files/xedor.pdfIn PDF document text
    • http://www.hausman.eu/images/wyswig_images/file/nexaseleve.pdfIn PDF document text
    • https://mokshadhamnepal.org/userfiles/files/21896934370.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/e1a4cf9bc65849f1b9c1e6e8c6da0c17/79839013178.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/5d206ae8ad40491a8d7ba8b2187ac397/40163740276.pdfIn PDF document text
    • https://rubin2000-distribuitorshop.ro/userfiles/file/jomevidabozabekar.pdfIn PDF document text
    • https://shriayurvednagpur.org/public/ckfinder/userfiles/files/86230109827.pdfIn PDF document text
    • http://konsultacjenaukowe.eu/Upload/file/nadida.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/358rmsakofqbped9a8hrprveb6/titekifebedaxisula.pdfIn PDF document text
    • http://monroehighwildcats.com/clients/40160/File/7237350675.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/7a940946bbe1d88a5f486b75077fc0cd/77884271620.pdfIn PDF document text
    • http://istrouma1971.com/clients/9/9b/9b88b062b8d6af44b28e209fcb06d7d5/File/71681743674.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/q3haur4oq0i8tftau8ut54voc7/muranalisotedawuguvafoj.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/8bac240c9c0004087139779e845369da/13083364231.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/l7dbumdecmh7s17ed7chp1es54/69820623465.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/75642043325.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/55750167927.pdfIn PDF document text
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/pisewiseguzezeka.pdfIn PDF document text
    • http://artdealer.vn/upload/fckimagesfile/88373c49ad7b7f93f702c7c76765f563.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_off0000e898.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE898 17884 bytes
SHA-256: adb997871eb071485a462add9a8e25ba313d4c0baf72423f5463dc70962bf692
font_01_sfnt_off000116d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012ee8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EE8 10580 bytes
SHA-256: c07d0d05bbd32b1d92263e8fabb6b9943d91738cf297af6842f352141b55982f