Malicious PDF — malware analysis report

Static analysis result for SHA-256 92bb70b13d50b8b7…

MALICIOUS

PDF

127.7 KB Created: 2021-10-06 09:19:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4e2e2e49e0543b9669bf8a7e936c438d SHA-1: 15bacad33bcb4f538ae0aa4de6f6122bf9113645 SHA-256: 92bb70b13d50b8b7550033b5d4a060b51e539d6f02a51ee5306f43675a513f02
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://archism.ru/uplcv?utm_term=iron+chest+forge PDF link annotation
    • https://www.stnedu.com/ckfinder/upload/files/21257433385.pdfIn PDF document text
    • https://safecampus.in/cmsCart/upload/file/gekibo.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16158f7b7970ea---gifom.pdfIn PDF document text
    • http://gzperson.com/uploadfile/files/75544181299.pdfIn PDF document text
    • https://gizaviation.com/uploads/files/vegal.pdfIn PDF document text
    • http://maxidmum.com/images/upload/fck/file/bogom.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/91167634189.pdfIn PDF document text
    • https://relans-nn.ru/images/docs/file/36062550316.pdfIn PDF document text
    • https://vongtaytramhuong.vn/upload/files/60661242606.pdfIn PDF document text
    • https://klcconsulting.eu/klc/file/setobuvufu.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/21044856943.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/peretojesixakiruveg.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/raporobidawuwekutujo.pdfIn PDF document text
    • https://mimpishio2.com/contents/files/56385432999.pdfIn PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/23702988780.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013/admin/ckfinder/userfiles/files/rumijopokasajeko.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/35087948555.pdfIn PDF document text
    • http://mgbig.com/upload_fck/file/2021-9-25/20210925174743360729.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/vodewupezapijipofo.pdfIn PDF document text
    • http://soojuspilt.ee/files/file/92386727923.pdfIn PDF document text
    • http://dsagco.com/Upload/file/96323812624.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/feffd3ead57496ee30bf20a80127beb4/85282406852.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16155ed5f5c96e---dinekoxod.pdfIn PDF document text
    • https://vaitinhdien.com/app/webroot/upload/files/ranudufe.pdfIn PDF document text
    • http://vit-physio.de/file/62831117183.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_off00018ae8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18AE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001a2fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A2FA 21424 bytes
SHA-256: bc5aa088ebe1906c12fc32fcb5c67389cc8211dd8a0d7b60ab869d2f42c5d0e1
font_02_sfnt_off0001d9e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D9E4 10264 bytes
SHA-256: a69c40ef1e5a1ea3678670683eb2366623fc7e5eebd79d61afd893437dd57bf0