Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a4a3f031257be4c…

MALICIOUS

PDF

93.1 KB Created: 2021-06-29 11:17:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b1f1bc9890aa826d684c9cca4a3c9007 SHA-1: 6157ea5e2fa6745be413bbf83dad519146078c52 SHA-256: 5a4a3f031257be4c4fa06be62812f4a76a20dcdc4d9c4d323718a9fddad36751
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, suggesting a link farm designed to distribute malicious files. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. No scripts were extracted, but the PDF structure itself facilitates the attack by hosting download links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9924

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075c240d2334---12397544625.pdf In PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078c432b2b8f---70716552953.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/i362v8126tkt4tik9qrn2bb4a7/93179964597.pdfIn PDF document text
    • http://woodsfamilypride.org/clients/2/2c/2c83419adcf4927d74d3defe18342386/File/fibewaxoguzosit.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16092e4ac9c7be---pilexef.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160864802c2ef0---mogexebap.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/160744a4e15840---fulematibazupo.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/1a5a5fac3befb261c10c42409fbe6ad3/43908418209.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee143eac14---83333004005.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/fopavufadivafinu.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/61732090414.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/8563b50db5a52694b67cf6c495551f5d/favuxujodijeruvetuwo.pdfIn PDF document text
    • http://uhy-th.com/image/upload/files/41722422000.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5cf977b2c---39889672410.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b48c7700a31---86759265111.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/xigexakinajadekanob.pdfIn PDF document text
    • https://aashianarealty.com/file/11632769730.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/g460n2h9n5og1gts71canprs4d/xodufijufudemofati.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/ha0c7ladjk4fp4jtuuhm096ceg/buvatoluxiz.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7ce55bb78---29288551301.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/f93e6cd8e154d5dae634fa071ad79918/buwusiko.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/e131eeedb941992b3ad9cb5a394009c8/76807192162.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/16098893f38bd7---44630227198.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/bokikafolomapu.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/852e8b7ec42ac3828444cc14b01f1391/melosirazikugifel.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=jason+todd+as+red+robinPDF link annotation
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f314.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF314 16296 bytes
SHA-256: dc973f96ffb519cc85163c7e9fc4ad3210cbabd63a0776608ee9150f0d5fd2ed
font_01_sfnt_off0001093e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1093E 10324 bytes
SHA-256: 8a91511a820a878868bdee4cda909f8e12efee2248a065604efa9864b6a1e0d5
font_02_sfnt_off000120ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000138c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138C0 17468 bytes
SHA-256: ae2dd83955089d5cf558511ae3714af5310f21799e8d1881762b0211ca33eb3f