Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a08cf7553d84a41…

MALICIOUS

PDF

85.7 KB Created: 2021-09-19 08:21:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7011a122556f1daad9d8bbf49a8cfa54 SHA-1: 1d668c11882ceb676771fa2b7c7991172254f1ea SHA-256: 5a08cf7553d84a41440bfdcefe3e02485df7998394727ea7365c04ac997316a4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://inwebjor.ru/uplcv?utm_term=resident+evil+4+apk+portugues PDF link annotation
    • http://www.luna1956.com/images/library/File/vilolufe.pdfIn PDF document text
    • http://pwr-tech.ru/userfiles/file/45623021812.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/45284038520.pdfIn PDF document text
    • http://www.scsk12.org/policy/files/files/zijifuv.pdfIn PDF document text
    • http://thucphamchucnangmy.vn/uploads/files/milidekaze.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/161387c8104d49---51551650918.pdfIn PDF document text
    • http://harposwebdesign.nl/app/webroot/files/userfiles/files/vemij.pdfIn PDF document text
    • http://asliev.coco1490.com/upload/file_folder/file/69870944266.pdfIn PDF document text
    • http://marikitaberbagi.com/userfiles/file/rorimoxemezuvavo.pdfIn PDF document text
    • http://peoplefineart.com/assets/202109/files/20210916172713724783.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131930ace678---44245556994.pdfIn PDF document text
    • https://estoniapools.com/contents/files/dufubejukatixet.pdfIn PDF document text
    • https://bunianco.com/other_files/File/gakidexurirejivo.pdfIn PDF document text
    • https://emenu.hu/editor_up/dewosetekonijivikovo.pdfIn PDF document text
    • https://dcicz.org/userfiles/file/fubomasomezejeg.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614685eb13523---39619932820.pdfIn PDF document text
    • http://centromp.it/userfiles/files/34455658621.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/670009b75bb31e1da5527645d01a3678/18499644437.pdfIn PDF document text
    • http://baove24h.info/upload/files/44332058856.pdfIn PDF document text
    • http://computergramm.com/userfiles/file/tevafoterasodabomu.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd7ac22b22---54061632820.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_off0000df38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF38 10948 bytes
SHA-256: afd88e397a0d222bd62307cc30fbd811cf36e5cdbe5de5971a05d9d659a3a47f
font_01_sfnt_off0000f892.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF892 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A4 21824 bytes
SHA-256: b2f61afb7de465c8549c2c93aabc2d5f5c28c9c74ee7eeb355e804c38513df4d