Malicious PDF — malware analysis report

Static analysis result for SHA-256 f23dc2349f17a5a4…

MALICIOUS

PDF

82.4 KB Created: 2021-09-05 08:28:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: d987d640faf0495f8edcdfd9ff05846b SHA-1: 7d3da26d520ed97b5886f3fc2001d6962d1b2ca2 SHA-256: f23dc2349f17a5a4155305d55b292e9c76165d6adc1ec1cc834737aaa38d3196
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://www.pharmawell.eu/ckfinder/userfiles/files/60411599038.pdf In PDF document text
    • https://bestcoloringpages.com/userfiles/file/marel.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/e00c73f4202b6d11e5ea7ba66e4b9a0d/gezun.pdfIn PDF document text
    • https://domilot.com/uploader/files/96689750024.pdfIn PDF document text
    • https://lacgl.org/upload/editor/file/natewe.pdfIn PDF document text
    • http://dgjinhak.kr/DATA/upload/files/202106300847488811.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210721013125527099tfr9rdjh0svr.pdfIn PDF document text
    • http://www.deopendeur.org/imgUser/file/resigawe.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160b42818360a4---karagiw.pdfIn PDF document text
    • http://nuestrasenoranm.org/clients/8/88/88a18899c67a61641ca1f7d027daa919/File/parugiwiluvegikisesefafuf.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/malexifezuwuw.pdfIn PDF document text
    • http://www.majbrno.cz/uploads/files/zokujumoneb.pdfIn PDF document text
    • https://inprovitcentroamerica.com/ckfinder/userfiles/files/67707243321.pdfIn PDF document text
    • https://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/dulafixizikeliw.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202108152314187726.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/8e5ec4400d6c155662b741964ee8c19b/60737577058.pdfIn PDF document text
    • http://inruho.ru/ckfinder/userfiles/files/sevesaref.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608731ba7db69---58308987110.pdfIn PDF document text
    • https://xn--hjrnskadeakademien-mtb.se/userfiles/file/gamomonapiwajujaveriki.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087b2ff413e2---pizupazadev.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/71deb06884abee6b848efb1919c815ab/rusisujurotejomowi.pdfIn PDF document text
    • http://nhactheducthammy.com/upload/files/7166670928.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=modificar+pdf+androidPDF 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_off0000d8fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8FB 10164 bytes
SHA-256: ae7a80909d22a29e2a25380028a2e20aec59efaa6e02b0101002f53227720d81
font_01_sfnt_off0000efc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC3 19836 bytes
SHA-256: 6ac29d0fcf9937f74c9b01413cf13656b6d9029511918a668e8b4552d665cb54
font_02_sfnt_off0001243d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1243D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1