Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d38ca78aeac57a6…

MALICIOUS

PDF

81.6 KB Created: 2021-09-10 12:49:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 8170141814ae739d9ae83dd7f18b6d8d SHA-1: 3b38952716252fd6eec418b30e06934ba115c70f SHA-256: 4d38ca78aeac57a625ed4230c1720ef38ca234b42c79fba6fbaf071f7c07e36f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that function as a link farm, directing users to external websites. Several of these URLs point to compromised WordPress sites or disposable hosting, indicating a malicious intent to distribute further payloads or conduct phishing. The ML classifier and ClamAV detection strongly support the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://infrive.ru/uplcv?utm_term=wpa+tester+for+android+10 PDF link annotation
    • http://wang023spa.com/userfiles/202109file/2021090608265970554.pdfIn PDF document text
    • http://video-cycling.de/files/file/2154091230.pdfIn PDF document text
    • https://ajansnigde.com/resimler/files/84624359067.pdfIn PDF document text
    • https://ccaquebec.com/userupload/files/86415872501.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a68b9f0724---ranono.pdfIn PDF document text
    • https://highrise.pl/file/21249835696.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/lowatositilobimozomu.pdfIn PDF document text
    • https://ou-ravda.com/ckfinder/userfiles/files/15815523125.pdfIn PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/tiweromimotof.pdfIn PDF document text
    • http://www.pibmg.com.br/ckfinder/userfiles/files/files/36029396765.pdfIn PDF document text
    • http://hyswimpool.com/userfiles/zemakotile.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/98dffc35c7a6db0a0ff4a13199bb662d/31847375357.pdfIn PDF document text
    • http://www.vnos.vn/app/webroot/uploads/files/gelorekigegited.pdfIn PDF document text
    • http://cesarrodarte.com/userfiles/file/suramudeloluvirosem.pdfIn PDF document text
    • https://feldmann-spedition.de/pics/userfiles/file/pafoxokekabegixutun.pdfIn PDF document text
    • https://istanajp.com/contents/files/63878303957.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/94428851520.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/6135509253.pdfIn PDF document text
    • http://pravkniga.ru/files/userfiles/files/46177662481.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131fe8aa155a---42156199937.pdfIn PDF document text
    • http://roletyhanarol.pl/files/file/nuxubiput.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/nonabaroratubizepu.pdfIn PDF document text
    • https://horgaszvelem.hu/ckfinder/userfiles/files/tadubutejuxoxi.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/96245414478.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3e3fef7e4---79226092187.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_off0000dc24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC24 10612 bytes
SHA-256: 9284a247c81e5ed8259812caccdbf228e924b7c32d911fb0aac716fac38afd8b
font_01_sfnt_off0000f499.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF499 16976 bytes
SHA-256: 3f0be0354063b6ba47a74587c0b5bae88cbae719f571cffc7d4dc4f92ba69acf
font_02_sfnt_off0001207e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1207E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1