Malicious PDF — malware analysis report

Static analysis result for SHA-256 728e90dae2ddc230…

MALICIOUS

PDF

80.9 KB Created: 2021-08-26 12:18:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 85398bd13c25b8b0f56e70a6bf01670e SHA-1: 53641f308b1da53628b8d9f72d2a5fff3de7589f SHA-256: 728e90dae2ddc2305e9f028c9a489088869dab445dec009f965c4e7c599ebc54
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable domains, likely intended to lead users to malicious content. The presence of multiple PDF link farm heuristics and compromised CMS upload links strongly suggests a campaign to distribute malware or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://alate.org/admin/fckeditor/editorfile/ludivaritejajar.pdf In PDF document text
    • http://detikakdeti.ru/img/file/ropubotinesibonok.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092692a5708c---kibitapazezexov.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e703c59295d---71436074654.pdfIn PDF document text
    • https://clubelsendero.com/img_pag/file/86837015277.pdfIn PDF document text
    • https://legend-chang.com/UserFiles/files/46640696592.pdfIn PDF document text
    • http://ronaldtan.nl/images/photo/76031107749.pdfIn PDF document text
    • http://hoclaixebinhthuan.com/upload/contentFile/file/94421340469.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a1887b4d78c---tumosirexevubunekuruxo.pdfIn PDF document text
    • https://amadesafar.ir/basefile/amadesafarir/files/23016987078.pdfIn PDF document text
    • https://burgas-remonti.com/userfiles/file/zaxulokukinivalodi.pdfIn PDF document text
    • http://asahiru-ban.com/files/files/xilonemoroderiribes.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16108bcbf4dcbb---semeribidi.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b436ce46c2f---81787579209.pdfIn PDF document text
    • https://megashina24.ru/files/files/tifotagemezurafibozurifa.pdfIn PDF document text
    • http://bukharasuwanee.com/sites/default/files/file/80359310162.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161243cabd3b9f---65035386237.pdfIn PDF document text
    • http://stattus.com/assets/file/getuwanowurotuz.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/117e130284adece56417ea6127b41573/mabonerebu.pdfIn PDF document text
    • http://cn-noah.com/uploadfile/file/pizareroto.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/tozipadigokatajosof.pdfIn PDF document text
    • http://stardentalcare.org/userfiles/file/pagekulivumorexobozojite.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=the+process+of+fractional+distillation+of+crude+oilPDF 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_off0000d705.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD705 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF17 16944 bytes
SHA-256: 2b8c1124c1826415c9ed357f2df07c8e9f91b0e50b367fa51ddb57cc5df5c4ea
font_02_sfnt_off00011b17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B17 10780 bytes
SHA-256: 84212a9a0cdfeac1cdfdf4cbcf6ec8a7bc603860f6570989ce36de51f306ea4f