Malicious PDF — malware analysis report

Static analysis result for SHA-256 c26b4581db8adb30…

MALICIOUS

PDF

80.7 KB Created: 2021-09-12 01:47:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: b6f4362414d39b93f7267b4c532e5b81 SHA-1: ad34ff35cf95a87eb5045c7a4e6a50255c5c8112 SHA-256: c26b4581db8adb30fadb88256ae10fe1290188419a0f81553f1180a31f8db39d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for a phishing trojan. It contains a link farm pointing to numerous disposable domains and compromised CMS uploads, indicating an attempt to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://mineraux-et-lithotherapie.fr/ckeditor/upload/files/36766177087.pdf In PDF document text
    • https://termofriz.rs/files/68713585786.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/80588452713.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16130f2a721d81---xobaferubusevewu.pdfIn PDF document text
    • http://realfootball.gr/userfiles/file/kifusuwus.pdfIn PDF document text
    • http://madiagranitosilano.it/userfiles/files/mupimuwok.pdfIn PDF document text
    • http://npcbalkan.net/ckeditor/ckfinder/userfiles/files/58725768343.pdfIn PDF document text
    • http://domki-kopalino.pl/pliki/22273195906.pdfIn PDF document text
    • http://avstralianature.ru/ckfinder/userfiles/files/23861248232.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/7f164bc93fd93b65afc424e5b58dd922/sefidojitiroge.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/e541c7960a161a3fdd84c309e0f5c769/puzazugasoxigi.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/887355f3e1cb90e0d1d6ebe4c635689e/molesonurosoka.pdfIn PDF document text
    • http://veraschwemmle.de/fckdata/file/21649642510.pdfIn PDF document text
    • https://varbackaforskola.se/ckfinder/userfiles/files/60974225049.pdfIn PDF document text
    • http://www.investinwielkopolska.pl/application/lib/ckfinder/userfiles/files/lixavazazugi.pdfIn PDF document text
    • http://sensitiva.fi/UserFiles/File/ziwevefemow.pdfIn PDF document text
    • http://elliptical-trainers.ru/ckfinder/userfiles/files/37737966300.pdfIn PDF document text
    • http://sensitiva.fi/UserFiles/File/fameturuwabutobogi.pdfIn PDF document text
    • https://pgp-puh.hr/fck_media/file/84551599498.pdfIn PDF document text
    • http://swapnakoodu.com/fck_uploads/file/40661783301.pdfIn PDF document text
    • https://eqonetech.com/upload/userfiles/files/44736019540.pdfIn PDF document text
    • http://protok.pro/upload/files/34249656636.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/161315b3a2df2f---96044882302.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/c0a084a8af6aa9f70333fc02abdf9834/bemaw.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/72850554175.pdfIn PDF document text
    • http://galsabino.it/userfiles/files/46949649321.pdfIn PDF document text
    • https://himarco.ir/basefile/himarcoir/files/gujekezotetotawupajes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=obb+service+is+running+appPDF 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_off0000d792.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD792 10616 bytes
SHA-256: 83a6310503a3563b61ec18cefad8a2eb04b42e6df350e68faa726f78e347ea7a
font_01_sfnt_off0000efdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107EF 17392 bytes
SHA-256: cf134a7c661cf887a57cc70d8553d0104e0a2b0f8f2ea3e4ebe3ef5c557cfe4e