Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6243ffc08505c49…

MALICIOUS

PDF

85.3 KB Created: 2021-09-16 21:35:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 443f37c58f8d1e65cd6cc443b597250d SHA-1: 6250c0852907f09da45d9312ed4fa91c4db87da1 SHA-256: b6243ffc08505c49f9f55e68c2619ef0ec267089af7dcf04f583db9c3c92487a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection to these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://garglob.ru/uplcv?utm_term=how+can+i+off+safe+mode+in+android+phones PDF link annotation
    • http://anael.fr/fckeditor/userfiles/file/mobifaf.pdfIn PDF document text
    • http://www.ishvani.com/www/js/ckfinder/userfiles/files/pozupuvapalolosasur.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/86823092540.pdfIn PDF document text
    • http://bayzones.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/difizimujovulizupanaxe.pdfIn PDF document text
    • https://mercerapparelss.com/userfiles/files/79473030878.pdfIn PDF document text
    • https://celebicatering.com/upload/ckfinder/files/wevoporobokotokip.pdfIn PDF document text
    • http://vanhacollection.com/images/files/rogekixevibimenon.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161422e3d663f2---luvitibakumoxafanus.pdfIn PDF document text
    • http://natur-pet.cz/webpagebuilder/ckfinder/userfiles/files/nejuwiwonodarib.pdfIn PDF document text
    • http://zopos.zohukum.com/ckfinder/userfiles/files/wutabejolitev.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/keminolupovi.pdfIn PDF document text
    • https://chulintemple.house-well.com/CKEdit/upload/files/75323910847.pdfIn PDF document text
    • http://warwick-ems.org/userfiles/file/14040011140.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/rodem.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613205ed4c804---80182466051.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/28927794843.pdfIn PDF document text
    • http://naphotelbangkok.com/userfiles/files/kuraparujemuvokarivori.pdfIn PDF document text
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/161327234287d1---90532377640.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/sekunonawefopolikijop.pdfIn PDF document text
    • http://studiotrusso.it/userfiles/files/13275535436.pdfIn PDF document text
    • http://m-styleauto.com/js/upload/files/mesuzujolajusulilaxuwolip.pdfIn PDF document text
    • http://zkqzl.com/uploadfile/file///2021090900473448.pdfIn PDF document text
    • 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_off0000e881.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE881 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010093.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10093 17620 bytes
SHA-256: 00cb535eed07eda929f38e183c527e770fc1c9bfb5c656fa1b6e3c4ab9a4b6cc
font_02_sfnt_off00012ea8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EA8 10816 bytes
SHA-256: d1e42bc86c9170e95a91414af4fd664f4fe8f9d352cbda1ed910ea641e0b8c4b