Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8cf67dec074dab2…

MALICIOUS

PDF

91.5 KB Created: 2021-07-05 08:48:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 29bc8659978d24dc1e820d65baa65e04 SHA-1: 1224054f315fbb02ca4f3de028de1779576971e5 SHA-256: b8cf67dec074dab2c1b4a842d9a7eb9f3baa493b59137e015ab0c907874470fc
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://anhopphat.com/uploads/files/jigojofoseture.pdf In PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4132c9fc86---nofokudakizutusizebowolum.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/dukawum.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a4e9991d2e---pikenawij.pdfIn PDF document text
    • http://tai-group.com/upload/files/gapafiladibujilo.pdfIn PDF document text
    • https://echipamente-scule.ro/userfiles/file/9964723464.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/gbktnjlh32vab2871ud6jnk047/kojetelipajodigeli.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb6e43abd8---narikakilavuvexiwawajet.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608f0765bde2e---18991719097.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/30260892480.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16084e8359daeb---gowalawe.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e66d549ce---27319445615.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160862bb3aa58c---62574437328.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea6376eca7---63716377468.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/27666557437.pdfIn PDF document text
    • http://vervesimuhub.com/userfiles/file/jezowofo.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/4347000a2c06abd6b52ba68575a8bb53/78733014862.pdfIn PDF document text
    • https://seikai.jp/free_images/files/91756561327.pdfIn PDF document text
    • http://grubstreet.ca/ckfinder/userfiles/files/99228211970.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/tevebobafig.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a29f49a4d79---nidakegajexaxib.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/luzoxepoxi.pdfIn PDF document text
    • http://sireny.net/share/files/pibaribabuxoxudolid.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/01def210c13b249eecaca2de671088fb/debirekofidovajufa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=eamcet+exam+2020+datePDF 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_off000103f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F3 17440 bytes
SHA-256: 3eebf74a7128865deb2596f035e1f4b0734a8276cab8a0c12af36c02affda108
font_01_sfnt_off000131e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000149fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149FB 10228 bytes
SHA-256: ada3fb1afea89a6d3d7c47e847288d88ff7df86714f4f6da9b08d92d65467b47