Malicious PDF — malware analysis report

Static analysis result for SHA-256 400bac68fd6324c4…

MALICIOUS

PDF

79.1 KB Created: 2021-09-03 08:05:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 81434c49c147e55ff2880742127578b6 SHA-1: d7ba4a500d9c2674971efaca89304fcf8355bc89 SHA-256: 400bac68fd6324c4c035ec504347357d5b84d2038f6689d9afee874dc591449f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. Analysis reveals it functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories. These links likely serve as lures to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/1f92097b3c18699e80f577520ff6b1d3/8397505285.pdf In PDF document text
    • https://sasalidayanisma.org/uploads/file/60565595939.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e31c16f2ff---83390456337.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/4u4k6tacqh8dnl1sghdnka2llb/wofugefob.pdfIn PDF document text
    • https://gw21.ch/uploads/userfiles/file/19664143183.pdfIn PDF document text
    • http://baybayankaauamo.com/clients/c/c9/c9e0f772d4a556598cfa564a27137582/File/25287493900.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076116fe8cea---wexigutewulebere.pdfIn PDF document text
    • https://legend-chang.com/UserFiles/files/91147121332.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/57586403821.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/1885840243.pdfIn PDF document text
    • https://agatanorek.com/files/file/dudomowejoxuvanasotufuwig.pdfIn PDF document text
    • http://ping-property.com/user_img/files/fufege.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607a77e1d6022---zevowegotovizif.pdfIn PDF document text
    • https://anthonygillant.com/userfiles/file/bagowitowetujevapefolole.pdfIn PDF document text
    • http://mrtowing.ca/Lawyers/userfiles/file/gudun.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ac91d7bf50a---kisusorejan.pdfIn PDF document text
    • http://ingfrimale.com/userfiles/files/6331138077.pdfIn PDF document text
    • http://sreema.org/FCKeditor/file/lozavet.pdfIn PDF document text
    • http://zetrade.cz/userfiles/file/41210581400.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/2dd177861afc4190dc35b9e6185583d1/gototinosudadoladarudo.pdfIn PDF document text
    • http://ajivikafinance.com/userfiles/file/xixig.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/wazitijikixibot.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/37272242227.pdfIn PDF document text
    • http://webursitet.org/Files/file/55091847073.pdfIn PDF document text
    • http://prunay-en-yvelines.fr/ckfinder/userfiles/files/wedimabuvuxino.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/pi2n3appsvlnqe9tqldhpereo5/rotukosurarogajem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=genome+wide+association+studies+pdfPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d0c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0C3 17556 bytes
SHA-256: 03c6ebdd86d0da35b609f79a639c7a8249201ec1740f891e8a75239aa9ce8657
font_01_sfnt_off0000fd94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD94 10860 bytes
SHA-256: df32d0cc39b27e190fad91ab26a510e5fbad1555b93c4aa4e8d0210b8303e598
font_02_sfnt_off000116c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1