Malicious PDF — malware analysis report

Static analysis result for SHA-256 ddfa96bbf0094805…

MALICIOUS

PDF

81.8 KB Created: 2021-09-14 11:26:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a068bc8ff9e925bc4562bf12ea4ea01f SHA-1: 9fea77d3bd807e247873a4ebf368ef539e7f1653 SHA-256: ddfa96bbf00948059d7b52adb0bc9b4d3b08c9d35f2fe5c9d36c30127271ab24
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised CMS upload directories, suggesting an attempt to distribute malicious content or manipulate search engine results. The ML classifier also flagged this PDF as malicious. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8014

Heuristics 5

  • 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 http://ukonlinedirect.com/userfiles/files/4927493004.pdf In PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/f2c8ad7738407a8db5219ef96e0fabfc/naxabikozofu.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136bec06dd4c---72009130863.pdfIn PDF document text
    • http://kaupa.cz/userfiles/file/niropisotuwoxip.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/milejuremonup.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613bedf02a84b---milefisexajunud.pdfIn PDF document text
    • http://bycongroup.com/UserFiles/file/80729477437.pdfIn PDF document text
    • http://irfanmakina.com/depo/sayfaresim/file/2841336374.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/25630626345.pdfIn PDF document text
    • https://hattoco.vn/images/ckeditor/files/vuvuzigemibe.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/novotivubilogonovamux.pdfIn PDF document text
    • https://blokhol.com/upload/files/82256708016.pdfIn PDF document text
    • https://cokhivietuc.com/img-vietuc/files/91780066082.pdfIn PDF document text
    • http://daiichihr.com/uploads/news_file/nudonumelomarageketetima.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/a3716fcb9434c8a881c8bdd40984fe54/82937397450.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/91832536780.pdfIn PDF document text
    • https://anmimar.com/royal/userfiles/file/ditezekeluko.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f76fb80ad6---daxizosiw.pdfIn PDF document text
    • http://vpecargo.com/userfiles/file/fufokijerefonojakuwoxixu.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/11456796668.pdfIn PDF document text
    • https://client-sms.com/ckfinder/userfiles/files/5517941348.pdfIn PDF document text
    • http://gloteckr.com/upload/editor/file/xufeletuz.pdfIn PDF document text
    • https://ww150001.linebot.net/upfile/files/20210914122153.pdfIn PDF document text
    • https://pcetravel.com/files/file/82656716734.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=contacts+from+iphone+to+androidPDF link annotation
    • 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_off0000e1f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F1 10868 bytes
SHA-256: c30419557f050ed69fe1ad457eb2b011b0150b06991635ad2e4960d3aaaa8a40
font_01_sfnt_off0000fae4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAE4 17844 bytes
SHA-256: 66a872b53d3536fc27e7099dd28ef9c56db8dcbcaa480437256a9dc7fe8366d7
font_02_sfnt_off000128eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1