Malicious PDF — malware analysis report

Static analysis result for SHA-256 539f474c5e1d8f6b…

MALICIOUS

PDF

72.6 KB Created: 2021-09-11 04:29:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b53e134f6b3c797839399a6eead6be6e SHA-1: ed5da6362aa1484236c9ef32cbe5e6d9e5cf49bf SHA-256: 539f474c5e1d8f6bde2d654d309820150b9fc018903c4ab1b060a6cf7b1feab1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating link farms on potentially untrusted domains, suggesting an attempt to drive traffic to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://avision-italia.com/userfiles/files/1948637023.pdf In PDF document text
    • https://nabijdefossa.nl/upload/files/regulop.pdfIn PDF document text
    • https://kermoulin.com/userfiles/file/53437010513.pdfIn PDF document text
    • https://coolingrealestate.com/your-home-cleaner/FCKuploads/file/92592780845.pdfIn PDF document text
    • https://cqc-material.com/app/webroot/userfiles/files/19868567395.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/s67bcn80mkqgh3klukcnrc8dkl/44540082731.pdfIn PDF document text
    • https://ccskin.com/geektic/files/purixobagenawobib.pdfIn PDF document text
    • http://meditopthailand.com/file/bebalafugi.pdfIn PDF document text
    • http://clinicaveterinariailmarzocco.it/userfiles/files/19330079083.pdfIn PDF document text
    • https://jhservice.net/imagenes/galeria/files/19336805637.pdfIn PDF document text
    • http://brukbet.com/user_images/file/76849562641.pdfIn PDF document text
    • http://wxbeimei.cn/upload/ckimg/files/202109081522374497.pdfIn PDF document text
    • https://www.aifimm.it/admin/inc/ckfinder/userfiles/files/lubarotofawedabag.pdfIn PDF document text
    • https://zoldlaptop.hu/ckfinder/userfiles/files/62653166584.pdfIn PDF document text
    • https://buyafranchise.org/files/files/32359080616.pdfIn PDF document text
    • https://banktapeunadana.com/tapeunadana/bank2/admin/userfiles/file/72792551071.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130404c754f2---xitexejarufobironawese.pdfIn PDF document text
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/zumubovafonaduwejixam.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/revasarifemuximoli.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/12311868565.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161346e9f3a104---degolevoxexuder.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/jerixabodusipafinugixipe.pdfIn PDF document text
    • http://portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/lonamip.pdfIn PDF document text
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/jeforozow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=download+edit+foto+apkPDF 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_off0000bd50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD50 15760 bytes
SHA-256: cb3a6b1e13f3284bfe2e776015bef3a0e1934a640a9a93c76027dd6a416e1ae6
font_01_sfnt_off0000e552.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE552 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fd69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD69 10400 bytes
SHA-256: e9ead1e3dcd7eaf4c8392627d723bc53c6b85280598dd8304619a53b706becca