Malicious PDF — malware analysis report

Static analysis result for SHA-256 38c73cd3ff5f7b44…

MALICIOUS

PDF

74.4 KB Created: 2021-08-03 00:12:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 1137320cf46a9530ca8bdb5f7b3a274b SHA-1: d185c320a9d39f88f319d1aae872b92cd515648e SHA-256: 38c73cd3ff5f7b4492917b5df8a206f1f2b48be39601432567f5d79242d8e625
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Several heuristics point to the PDF acting as a link farm, with many URLs pointing to compromised WordPress sites hosting further PDF files. The presence of embedded URLs and the nature of the heuristics suggest this PDF is part of a phishing or malware distribution chain, likely intended to lure users into downloading additional malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1608a2a2277cc1---25002127683.pdf In PDF document text
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/49dks6e9rooc5prbkret6l6b9h/83294336053.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/u9o0c2o2ktg5glotehn6t2jvr9/6743031101.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/668f41f9f91ef4281f88ded0c9ccc605/bebadutadozaposifajej.pdfIn PDF document text
    • http://ansonseatery.com/uploads/files/zudowavat.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160babc3d657f1---sefunix.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb31d1d7d8---mesoz.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/jifereb.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/81690597297.pdfIn PDF document text
    • http://yesilkoyluleriz.biz/resimler/files/ziler.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/3fb817640ed9bd93a1dd1746008e8572/gevuf.pdfIn PDF document text
    • http://gima.ge/admin/ckeditor/ckfinder/userfiles/files/vazixifepatapopubikol.pdfIn PDF document text
    • http://mariopresto.pl/userfiles/file/90816398726.pdfIn PDF document text
    • http://sns.hu/_user/file/mopubomazekixejomuviv.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/93478381170.pdfIn PDF document text
    • http://bscsaoner.in/ckfinder/userfiles/files/3695737683.pdfIn PDF document text
    • http://tai-group.com/upload/files/13832751588.pdfIn PDF document text
    • https://iaido-iaijutsu.ru/userfiles_exc/zolonotorakaxir.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a9ab09f9f---mulivewinederasifimibala.pdfIn PDF document text
    • https://pearproperties.in/userfiles/file/66922515470.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/31384990444.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=calcular+el+area+bajo+la+curva+calculo+integralPDF 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_off0000bf1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF1C 16540 bytes
SHA-256: acabedbe15d6ccb493527a98acbff6a1f86921ad4ac431e7946769dcc7ff7a93
font_01_sfnt_off0000e8cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8CC 10704 bytes
SHA-256: 8a161a7d6410a78af8f44db5ad250bfd20dd911c0c0da0b08e8127bc89f5ffdb
font_02_sfnt_off0001017b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1017B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1