Malicious PDF — malware analysis report

Static analysis result for SHA-256 815b549472a1930b…

MALICIOUS

PDF

93.8 KB Created: 2021-09-15 14:18:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5d2cb43a3208f5274005bb93f58c5701 SHA-1: 0576844eb59e5b0645ba396afabf805fdfb6213f SHA-256: 815b549472a1930b60268d468c201a3cb5a9c3d30143af515d08f3445961fbba
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many hosted on compromised or disposable domains, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to deliver second-stage payloads or redirect to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://krisoc.ru/uplcv?utm_term=am%C3%A9lie+full+movie
    • http://shop-exclusive.cz/userfiles/file/zugesigoduxaxivupi.pdf
    • http://xn--krmer-dnnebacke-1kb72b.de/files/file/83880372248.pdf
    • http://gillsandgeckos.com/userfiles/file/modomigako.pdf
    • http://marsalanoleggio.it/userfiles/files/niwener.pdf
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/gcmplmtum7qfpuqd5i2l3r0mp1/82320088224.pdf
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/26e0e840ddf59e3353f5f54f5df28f9f/78739087457.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613090cd8002b---31207043929.pdf
    • http://resortvillairene.it/userfiles/files/gikumomidus.pdf
    • http://www.sec-ollivier-associes.fr/www/upload/file/16028426668.pdf
    • https://yam-token.com/business_school/uploads/file/remafik.pdf
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/6jmii1qpl89eecshlsqnuh85b5/zezumiwekifas.pdf
    • http://ucokampen.com/media/files/rominuzezimobilenu.pdf
    • http://baovecongtruong.com/upload/files/dokupop.pdf
    • http://hide-bo.com/img/tmp/file/wokuzabemojenapisirare.pdf
    • http://laros.cz/UserFiles/file/lijaloretulajivegi.pdf
    • https://ebooksweb.net/files/file/gofugonutabuneno.pdf
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/43102186959.pdf
    • http://styrexon.cz/userfiles/file/fejazibomupopelavenof.pdf
    • http://jpind.pl/userfiles/file/vutumevikaxaporawe.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/bf2ace1a49765023aa9896d5b58a2ee1/76967699804.pdf
    • https://confeccionesruiz.cl/UserFiles/File/79852165432.pdf
    • http://rurisnet.org/images/file/93093382598.pdf
    • https://babetravelling.com/ckfinder/userfiles2/files/75783055796.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010d24.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D24 16792 bytes
font_01_sfnt_off00012536.bin
d8286b5aae2feb690b91bef502d95aa691750d94eca33a3861ab3adca191b8a8
pdf-font-stream PDF embedded font (sfnt) at offset 0x12536 17368 bytes
font_02_sfnt_off000151eb.bin
4631ad276de829dd9e5c9ec92cfa2cd3e5ee148e37a1539a810c482e3b4df544
pdf-font-stream PDF embedded font (sfnt) at offset 0x151EB 10044 bytes