Malicious PDF — malware analysis report

Static analysis result for SHA-256 621be1a80e1baded…

MALICIOUS

PDF

71.0 KB Created: 2021-09-03 04:59:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 2c228908967a0f0594bf0e37c879d777 SHA-1: ccf6b3d768fe82dc1d8f59dbded83163220f7ac3 SHA-256: 621be1a80e1baded9bccc90cd2d1d349165be3218c3c2ae0dff4458011ae9d49
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically as a phishing or trojan. It contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of these links and the overall detection pattern indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://crewmak.ru/uplcv?utm_term=convert+kindle+book+to+pdf+on+mac PDF link annotation
    • https://quaint-house.com/55468526258.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609aecd052c58---tetap.pdfIn PDF document text
    • http://noithatnhapkhaugiasi.com/luutru/files/jagenukijuvenutobigos.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/94310983665.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/d7bc527dc05282fa1cc2f5afe2e16eee/49892179741.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608befd021f5e---wijiwuzedawidado.pdfIn PDF document text
    • https://akemi.ro/hirek/file/25559388685.pdfIn PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/883be0164b6232b38d8344bec6e157c0/73187437470.pdfIn PDF document text
    • https://prairieroseclothiers.com/FCKeditor/file/70819080122.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607696aecf564---23689582099.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/97838916470.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/rirarifizodijagora.pdfIn PDF document text
    • https://hosvagyok.hu/userfiles/file/63318430421.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/dugogofarezoz.pdfIn PDF document text
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/a34158ed03e93cf12d194bacbb569f11/13152297746.pdfIn PDF document text
    • https://t2sc.me/userfiles/19785855849.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/84074429893.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0b3057c66---besusabenuw.pdfIn PDF document text
    • http://wu-pao.com/upfiles/editor/files/tubuwerozok.pdfIn PDF document text
    • http://villa-margherita.biz/userfiles/files/41273697520.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/fa6d8415b3910b9d2730a27b37ff922d/7227901518.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_off0000b45c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB45C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC6E 16124 bytes
SHA-256: aade233c3f548ef23a09d0ca469ce5cdbff18ad424737cc5ab7de149500e98db
font_02_sfnt_off0000f5d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D8 10940 bytes
SHA-256: f17d28c9856543d0f738c4da8bfe8d46b175c5eeacf77e473f309035cdc7da9f