Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7b1802c5971961e…

MALICIOUS

PDF

93.1 KB Created: 2021-09-18 13:02:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 19192f25d7850cd7d19fa8f97f8a1e1b SHA-1: ff605286eb64b8e936db0de8913297ed4d9c1450 SHA-256: e7b1802c5971961ed6b8e96620f8d57978f9506d01d912214a834a03433346d5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The ML classifier and ClamAV also strongly indicated maliciousness. While no scripts were extracted, the presence of numerous external links suggests an attempt to lure users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://catamma.ru/uplcv?utm_term=opengl+es3+0 PDF link annotation
    • http://patriabrno.cz/userfiles/files/33545085105.pdfIn PDF document text
    • https://506hlapeta.com/files/file/lesim.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/lekidokate.pdfIn PDF document text
    • http://www.enfersalus.com/ckfinder/userfiles/files/32461247064.pdfIn PDF document text
    • http://otestmanager.org/club/data/userfiles/file/20210918162755.pdfIn PDF document text
    • https://sintasyapi.com/img/userfiles/file/rogaxawow.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/ic5qgtm8d86vkch5m7h8lbmv24/63881640022.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210905081617.pdfIn PDF document text
    • https://annekienlen.fr/imagesfile/bikudubusumisolibim.pdfIn PDF document text
    • https://eminencesolutions.in/resources/userfiles/file/nodofu.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210903_C9D5303BA59E4C94.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613b38b4d9fd7---widetof.pdfIn PDF document text
    • http://studiogaleazzo.eu/userfiles/files/rekobosifovepi.pdfIn PDF document text
    • http://www.srijonihealinghome.com/fckimages/file/12203890946.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/fezeruxekawixopediwozeg.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210909225350.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161300a1c64202---97323773018.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/80264968125.pdfIn PDF document text
    • https://heart-calligraphy.com/uploads/files/202109110904008537.pdfIn PDF document text
    • https://abcoegypt.com/userfiles/files/63010074552.pdfIn PDF document text
    • https://www.truckersplantparts.co.uk/ckfinder/userfiles/files/nufilevujixuguzavixa.pdfIn PDF document text
    • 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_off000108e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108E2 18132 bytes
SHA-256: 890731de3f8105ff326fe90f4d7bd2316916430804143a28c472e43064db94ce
font_01_sfnt_off00013876.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13876 10172 bytes
SHA-256: 4541f68cf95ea47b1cc2a79f5e652423a7ebaf3b90a5eb37af930eedd5bb54e5
font_02_sfnt_off00014f67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F67 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1