Malicious PDF — malware analysis report

Static analysis result for SHA-256 348f9aa7cf5d6392…

MALICIOUS

PDF

85.7 KB Created: 2021-09-08 17:06:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d2503e659b5ce0be4f1ee52575399f66 SHA-1: 3366721ef7e8a8871c9688c333ba49bea0449505 SHA-256: 348f9aa7cf5d63926bd3962afd2a26a4f67a8c1b3ff00c52db54422908261fdf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links indicates an attempt to direct users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://synerhu.ru/uplcv?utm_term=homocysteine+test+pdf PDF link annotation
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130425b19125---48197215957.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/1706879ccb55bb8802cbd9c993bc2cd7/22277028949.pdfIn PDF document text
    • https://pecintajp.com/contents/files/gasuzugu.pdfIn PDF document text
    • http://huynhgiabaohotel.com/uploads/FCK/file/vosumabanolerevi.pdfIn PDF document text
    • http://slhospital.com/upload/fckeditor/file/68803901689.pdfIn PDF document text
    • http://belv.ru/userfiles/file/22144555781.pdfIn PDF document text
    • https://birudongker.com/contents/files/54278755529.pdfIn PDF document text
    • https://alstar.uz/images/shared/file/zarowu.pdfIn PDF document text
    • https://truongthanhco.vn/webroot/img/files/25135772267.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/16132c76cd7233---lebonaxiputamogoto.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/nonizodanixemufukowup.pdfIn PDF document text
    • https://drisraadentalcenter.com/userfiles/file/tilepumav.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16138529c1a2c3---93876431648.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/fetosuzorufa.pdfIn PDF document text
    • http://charivne.info/images/file/77391336255.pdfIn PDF document text
    • http://cesurmakina.com/userfiles/file/lusoza.pdfIn PDF document text
    • http://www.ez4parcel.net/upfile/files/2021/09/07/saxukajop.pdfIn PDF document text
    • http://mgocsm.in/userfiles/file/xogomarasatuvijeriso.pdfIn PDF document text
    • http://retailcop.ca/files/95103407578.pdfIn PDF document text
    • https://immsac.pe/sgi_userfiles/userfiles/files/32757654620.pdfIn PDF document text
    • http://shannonlakeestates.org/fck_images/file/jepifig.pdfIn PDF document text
    • http://asorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/12334401021.pdfIn PDF document text
    • http://hatdesechia.com/storage/ckfinder/files/6087598208.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_off0000ec06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC06 10576 bytes
SHA-256: 978618c7cf136249bad7fab3f8beeecc75ec231b83e88d77a271e142f7c66bcd
font_01_sfnt_off00010422.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10422 17728 bytes
SHA-256: 80d91358200c3f9ab5c3d556e2b8710c73fef6f056b914ac918dfa1473dc66f5
font_02_sfnt_off00013127.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13127 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1