Malicious PDF — malware analysis report

Static analysis result for SHA-256 42f31c7dad265378…

MALICIOUS

PDF

75.8 KB Created: 2021-09-16 09:06:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f812b221c4c283b8b122754ebfac83ce SHA-1: 8835fd378bf13b6b7cd4861cb967e7a6580fdf89 SHA-256: 42f31c7dad26537819c54ad04abb887ee644ef5c7499a280eb38ddeaa107d158
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to compromised WordPress upload storage, suggesting an attempt to distribute malicious content or phish users. The presence of numerous unknown URLs further supports this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d73982f242---41999353189.pdf In PDF document text
    • http://cleversystems.ru/userfiles/file/kupexejasezuvajukoxal.pdfIn PDF document text
    • https://vinatech.com/userfiles/file/tizudukuruwuzusemaxepopu.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/73403793836.pdfIn PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/86142002354.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/roxokam.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/dc5728d854ad444b317926a10e45f3cd/78583926048.pdfIn PDF document text
    • http://nceed.kr/pds/userfiles/files/34301835895.pdfIn PDF document text
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/ketojigemo.pdfIn PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/nijidisad.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d8a4bc9c77---42730689296.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/3985061543.pdfIn PDF document text
    • https://micsys.in/userfiles/file/mipogaxazopixexuv.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/60180644987.pdfIn PDF document text
    • http://tindangnhadat.vn/upload/files/mirogusimolotofok.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/b098e88938b8695ef63112860a999795/36345917895.pdfIn PDF document text
    • https://suacuasathcm.com/uploads/files/65740323192.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2c2644d81---33183028819.pdfIn PDF document text
    • http://veszpremkosar.hu/_user/file/9965815949.pdfIn PDF document text
    • https://hobbypet.cz/files/file/mobemojewazapikilorazef.pdfIn PDF document text
    • https://aucordechasse.fr/vosImages/kizirinelapaxu.pdfIn PDF document text
    • https://stka.gr/ckfinder/userfiles/files/legewuloriroroduza.pdfIn PDF document text
    • https://agros.net/uploads/file/bevomiwimakoxejolabi.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/56496410506.pdfIn PDF document text
    • http://abwclayton.com/uploads/files/dafokefogomivekideba.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=jw+alive+hack+iosPDF 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
stream_005_off0000f341.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xF341 17740 bytes
SHA-256: dba3a13c1a9962991853035cedad690dc82d61fab25bf79032e302082eae7fd5
font_00_sfnt_off0000c3ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3EA 10260 bytes
SHA-256: 76752ce3e561caaa7b77673b5438ea45c8869a6dafa116d00eb9f08b94cb7541
font_01_sfnt_off0000db2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB2F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1