Malicious PDF — malware analysis report

Static analysis result for SHA-256 d23af3b1055c5b29…

MALICIOUS

PDF

75.3 KB Created: 2021-09-01 12:43:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 24c8ebaa878cc7b98b19b98f67b17d06 SHA-1: a89a9df72019628a38626c60191d6cc7cc808a5e SHA-256: d23af3b1055c5b2968e656ca444cc9d232aa076ad03e7c2196908ffcfce7d7f9
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to domains that appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' suggests links to compromised WordPress upload storage. The ML classifier also flagged this PDF as malicious with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://cnex.cc/images/blog//file/ridurosotafomedo.pdf In PDF document text
    • http://bogaarchitetti.it/userfiles/files/83817171353.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/7ef80a171c8e61be0667dfdbbfb4f1b5/58440198383.pdfIn PDF document text
    • http://rustproofingottawa.com/userfiles/file/82719358888.pdfIn PDF document text
    • http://lookkorea.net/userfiles/file/maretofumekizupesupowazi.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16086fb7bd2fdb---14159326212.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16084b0f2bebb0---sidusut.pdfIn PDF document text
    • http://goldenteriyaki.com/uploads/files/zukupazovosowosawuwuw.pdfIn PDF document text
    • https://dodomacnosti.net/data/file/tozuluz.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/75922296697.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/187mghgpp1kkhrk9rco8pmn9en/zekegabog.pdfIn PDF document text
    • http://interno-kazan.ru/upload/files/89752606781.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/6b0933ebc520425e6f73445bcbeb0ef6/41944613391.pdfIn PDF document text
    • http://szentistvanpatika.hu/upload/file/gemidamonegu.pdfIn PDF document text
    • http://ordineveterinarivenezia.eu/userfiles/files/muvisosufelupalesizet.pdfIn PDF document text
    • https://yukkumpulgroup1.com/contents//files/59597230585.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0600afc16---52558682373.pdfIn PDF document text
    • http://gtshotel.it/images/file/winenogefiferakevi.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/v57jjs7qpl4kfj1oksc59qn3d8/13553485744.pdfIn PDF document text
    • http://rancholasmonturaspremios.com/campannas/file/72826471487.pdfIn PDF document text
    • http://ypperfect.com/ckfinder/userfiles/files/43599104408.pdfIn PDF document text
    • https://emotionalgift.com/ckfinder/userfiles/files/91847219.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=fundamentals+of+logic+design+7th+edition+solutionsPDF 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_off0000c3d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dbed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBED 10948 bytes
SHA-256: f8a1f3a372804f0252cc531613ad90dd933f1e8915577f79f989622f8a0f3a82
font_02_sfnt_off0000f4f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F1 16400 bytes
SHA-256: afcfcc2bdfc7f4909538021afbbf932376607a0a8e27a853e872a1c71b4513d0