Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b4d23c3542a6520…

MALICIOUS

PDF

81.7 KB Created: 2021-09-08 16:30:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: e1c472a6159915f89e8f54bf10617ba2 SHA-1: 9aa97ac0432223c51d68df7c240c2b084ce69dd6 SHA-256: 1b4d23c3542a652047ed82ba0420bf2f48db75acc956ed7d7ed234f9ef2431d6
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 0.9911

Heuristics 7

  • 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.
  • 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://yildizteknikelektrik.net/resimler/files/50818641749.pdf In PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/o7jhnuvp0s3vbbac1ipr5cilsi/4831546578.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161382aa703ba6---62327836259.pdfIn PDF document text
    • https://badrivishal.com/media/56594153318.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a66b54fe8---74101629980.pdfIn PDF document text
    • http://bharatandcompany.in/ckfinder/userfiles/files/kelane.pdfIn PDF document text
    • http://huspanda.com/data/ckfinder/files/85615718182.pdfIn PDF document text
    • http://www.gc-antey.ru/ckfinder/userfiles/files/38860278290.pdfIn PDF document text
    • http://ngor2-3.com/file_media/file_image/file/87795586347.pdfIn PDF document text
    • http://beautifulmoda.com/userfiles/files/bidufavuliwigireberi.pdfIn PDF document text
    • https://bulendengin.com/upload/ckfinder/files/gituduvupoto.pdfIn PDF document text
    • https://www.habitat-morvan.fr/ckfinder/userfiles/files/92156095938.pdfIn PDF document text
    • http://pokrowce-ochronne.pl/Upload/file/49591800213.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/dtqh7d17svdea2ei95hk0sc5j4/bakowakise.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/81d0a965511fd6b50abe1865aceb4a3b/64957449618.pdfIn PDF document text
    • https://pchome.uzai.ca/upload/files/36943083413.pdfIn PDF document text
    • http://kawana.tech/userfiles/file/lokuzixi.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///vadakilojuzem.pdfIn PDF document text
    • http://billagelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tofifonejagedi.pdfIn PDF document text
    • http://giaydantuongphongkhach.net/images/news/file/wogorafetizonoraj.pdfIn PDF document text
    • http://hexindechem.com/upload/files/befanolezolidali.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161303d276c934---sumijexokojotefidixeted.pdfIn PDF document text
    • http://kingkady.cn/uploadfile/files/bakagapisujix.pdfIn PDF document text
    • http://rescue119.org/userfiles/file/sesefabi.pdfIn PDF document text
    • http://rootbeadmill.com/upload_fck/file/2021-9-6/20210906202253858475.pdfIn PDF document text
    • http://gsmontaggi.it/userfiles/files/xaxotasutaruv.pdfIn PDF document text
    • https://coevent.ru/upload/files/vakuduzupikowizubidiraj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=wireless+electricity+pdf+downloadPDF 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_off0000da15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA15 18036 bytes
SHA-256: ba4cc3d5c1978ed37ce6056f7bf30a3a579b54dbcb520a250c1552aa86eff017
font_01_sfnt_off0001079a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1079A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FB1 10808 bytes
SHA-256: c20b27b1ccbee99bcfa9dd4b83491761525cc9e47f4bcb902ff9234e109f9ef1