Malicious PDF — malware analysis report

Static analysis result for SHA-256 65904365666bcafd…

MALICIOUS

PDF

87.9 KB Created: 2021-08-07 01:33:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 5b8bbeae97bbc46954c69a9aa4a023bf SHA-1: 536b35f2b57f3b908ca8f640908293e113ecc908 SHA-256: 65904365666bcafd58c076225ffbf827df6ada99ae3efb083c9a462566314025
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document's primary purpose is to host a large number of links, potentially for SEO manipulation or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/afe15ce222fe0595996a2091a43f78f5/rekuseg.pdf In PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d69081d8f---71765941494.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/c019bf347d22748bf740512225adc6f8/90702896999.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7a8d9b070---48247735443.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/67ff4fc31480811cc23aa926c7de4a2d/32055121460.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/joxejo.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/jusirezoxozamusubew.pdfIn PDF document text
    • http://vishwkarmaenterprises.com/webroot/img/userfiles/files/11639576261.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1610da39d79115---74958543217.pdfIn PDF document text
    • http://gulfcoolcontracting.com/uploads/userfiles/file/file/gavavexovofemimigaxodeda.pdfIn PDF document text
    • http://malverne69.com/clients/a/a7/a743c233813d1a1dbf5c38c484d85cdc/File/punajazesawukutemeja.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/76b832699c7995854a4d7f293d54a375/wurudeniporuzov.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a8be3ece5a---batilofudixon.pdfIn PDF document text
    • http://sentezetutmerkezi.com/upload/ckfinder/files/dagawir.pdfIn PDF document text
    • http://kovacsoltvaskerites.hu/images/file/85502563497.pdfIn PDF document text
    • http://www.bluewhaleline.com/image/upload/File/fovelukumujupaba.pdfIn PDF document text
    • http://smithmaloney.com/clients/3/32/32eae1a42220421eddab78da2f55685d/File/buwisoki.pdfIn PDF document text
    • http://euroear.eu/ckfinder/userfiles/files/39278704889.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d7a1be53304---22130882577.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160751a28da26e---72213210712.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/e43bf2d0b1bd91cd4dd8f08e9fec723d/31834891061.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e6ff0dd17---6601966515.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/9jtdtqg63kl3trhuu7gcc67337/44279622902.pdfIn PDF document text
    • https://rocksoliddesigns.biz/userfiles/file/97951544046.pdfIn PDF document text
    • https://vestol.bg/files/file/janumalawo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=world+conqueror+3+mod+apk+unlimited+everythingPDF 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_off0000ef8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8D 17716 bytes
SHA-256: a4fa7ae095fbbe1db041505536e76685f87146015801a38eb9b397ce85d13a12
font_01_sfnt_off00011e3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013652.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13652 11476 bytes
SHA-256: 6b22c0d4afd0fc4df6f608d3d60feade561204757f9e76dd208a579835cbdd05