Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a7d09207cce86b0…

MALICIOUS

PDF

81.9 KB Created: 2021-09-18 03:59:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: bffdd6e02fb4cd0cc24d16a51dd120cc SHA-1: 66ca488afd8fce7c410a64e5e14529635acd2ea6 SHA-256: 5a7d09207cce86b084c9bec5e0c3fd4e7ed3f84be8dbe7a38e59a997a2ed72a1
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites and other potentially disposable hosting, suggesting a link farm designed to redirect users. The presence of external URIs and the overall structure point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ruh-center.ru/userfiles/file/97590714138.pdf In PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135f64e2d0bd---lozusunaki.pdfIn PDF document text
    • http://wonikquartz.com/upload/editor/file/1630987058.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/e6b956ab446514c7f6a4bc3c21bc9534/pexiku.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/161338de8dd7e1---diwim.pdfIn PDF document text
    • http://ilink.pl/userfiles/file/8032071553.pdfIn PDF document text
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/55182521685.pdfIn PDF document text
    • http://csc021.com/userfiles/file/20210911154450_m6tbab.pdfIn PDF document text
    • http://www.vegagastro.pl/upload/file/judisakopadanazitud.pdfIn PDF document text
    • https://mariapolis.es/ckfinder/userfiles/files/rurovowajaxixowefutukum.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/44798659156.pdfIn PDF document text
    • http://mtreurope.com/ckfinder/userfiles/files/xumawetikixele.pdfIn PDF document text
    • https://ichapps.peaceofworld.com/ichapps/ckeditor-ckfinder-integration/uploads/files/37988024019.pdfIn PDF document text
    • http://abwingsde.com/uploads/files/kodos.pdfIn PDF document text
    • http://hoclaixebinhthuan.com/upload/contentFile/file/64502351544.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/161407e6a0733b---wulemu.pdfIn PDF document text
    • https://beytarimcilik.com/admin/editor_resim/file/sakotibofonazebuku.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/a3ebed861e5d2b1cb1d6f71cc8ed93c0/zibub.pdfIn PDF document text
    • http://esejsc.com/upload/files/64773333973.pdfIn PDF document text
    • https://theloneranger.tv/clients/loneranger/ckfinder/userfiles/files/fegowasitek.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/a5231402dc29528ecd734b455bbd4ab5/39721497745.pdfIn PDF document text
    • http://les-dvorik.ru/userfiles/file/99889020159.pdfIn PDF document text
    • http://cascad-trans.ru/files/9956726935.pdfIn PDF document text
    • http://vers-ma.de/userfiles/file/86718741822.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=mp4+to+3gp+video+converter+apkPDF 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_off0000da25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f23c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF23C 10876 bytes
SHA-256: 1c3091e38fbfbf07901b676a61df2a0b050731902846ff6ccb8c1d5e906e9f50
font_02_sfnt_off00010b65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B65 17700 bytes
SHA-256: d52fdbd4b12f456c1c75a105298721ea74630719ac2449751ad2f22c90182fb9