Malicious PDF — malware analysis report

Static analysis result for SHA-256 665e8426be236f2c…

MALICIOUS

PDF

77.0 KB Created: 2021-09-17 15:02:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 061f5eab22c781c3d84b8df77ad0d049 SHA-1: 22c8a3ec11917859b0c9e2371d1dff1d4a9c3cc9 SHA-256: 665e8426be236f2ccc98f3b8e92c4c556ae5d939ecd9f6671fccfd10c805656e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains multiple links pointing to potentially compromised websites, indicated by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded URLs are designed to redirect users to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • 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.
  • 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://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/e3df5798a7868fc411d033b70e44781a/63087867578.pdf In PDF document text
    • http://zaiger.ru/img/file/zadiritosu.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/10669085385.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b4f43b9ef---lozumaberimotewowejiw.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/dawirut.pdfIn PDF document text
    • http://vinhthuanvietnam.com/upload/files/59590698139.pdfIn PDF document text
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/diwuboberupikivudaweko.pdfIn PDF document text
    • http://rabotatver.ru/userfiles/admin/gawulilekukugesegufumezop.pdfIn PDF document text
    • https://accidentmatters.com/ckfinder/userfiles/files/18635368278.pdfIn PDF document text
    • http://helenhotel.vn/upload/files/8518449866.pdfIn PDF document text
    • https://pasarangroup1.com/contents/files/26338146578.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/rubazujijobumibefo.pdfIn PDF document text
    • http://royalleasingny.com/admin/images/file/57871237234.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16132b19d80d5c---komofakazum.pdfIn PDF document text
    • https://garraldaarquitectura.com/garralda_userfiles/files/gumigewufifovoxosifaj.pdfIn PDF document text
    • https://jamisonfurnace.ca/userfiles/files/45000285532.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/12261774645.pdfIn PDF document text
    • http://droprint.my/home/ququ4923/public_html/userfiles/file/wowujuwowene.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/79008501027.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/85347599767.pdfIn PDF document text
    • http://queenart.kr/userData/board/file/roguzose.pdfIn PDF document text
    • http://www.sictombbi.fr/ckfinder/userfiles/files/8733549457.pdfIn PDF document text
    • https://needletherapy.eu/upload/file/13010018832.pdfIn PDF document text
    • http://satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/rakixil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=bully+anniversary+edition+apk+obb+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_off0000c420.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC420 18860 bytes
SHA-256: 7c089ed35da2569fb49749c7a1d08108799e2c37b2a09ba8c68e08e4b276396e
font_01_sfnt_off0000f4d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ced.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CED 11036 bytes
SHA-256: 3135fb50738985f537e58ae1d87dca7ef4e86ee9fba2d78d9a1bee6d7cca670a