Malicious PDF — malware analysis report

Static analysis result for SHA-256 d57ac25ab66f9862…

MALICIOUS

PDF

71.6 KB Created: 2021-09-20 18:20:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6a7cf558514f4e237172299cf0350920 SHA-1: fd34e64295452689155d8eba59865baececdf76b SHA-256: d57ac25ab66f9862bd1195e2614b253247fb403a2982d0a97ecc41b65ef6fc81
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external URLs, some of which are hosted on compromised or disposable domains. The presence of numerous links, including those pointing to compromised WordPress uploads and disposable hosting, strongly suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://alebusph.centralcms.cloud/galeria/files/88713296240.pdf In PDF document text
    • http://melly-incendie.fr/img_db/dezew.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143ca212c99a---96867387737.pdfIn PDF document text
    • https://haysalon.com/public_html/userfiles/file/wironeketamamolakanifofuw.pdfIn PDF document text
    • http://dija.lv/public/userfiles/file/45029102390.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/josazojole.pdfIn PDF document text
    • https://estudiowebcolombia.com/ckfinder/userfiles/files/fokasukad.pdfIn PDF document text
    • https://phatgiaolongan.com/upload/ckupload/files/nujadaribudezuker.pdfIn PDF document text
    • https://oferta.lt/i/File/5855671368.pdfIn PDF document text
    • http://csc-vietnam.vn/uploads/userfiles/file/goxifomewojatixidekasi.pdfIn PDF document text
    • http://yotlist.com/uniformkontakt/userfiles/image/files/gosuxawi.pdfIn PDF document text
    • http://bestofbeer.ru/ckfinder/userfiles/files/fakatuxujabok.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/kulowu.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/pakosawebeliromudowifir.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/d25a698a0d69debbfa7a523dc6a3fa07/86762325002.pdfIn PDF document text
    • http://www.alexgis.com/siteuploads/editorimg/file/xiwokilekodekilaj.pdfIn PDF document text
    • http://zhymwz.com/upfile/file/61930194185.pdfIn PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/94407244168.pdfIn PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/kutisebizafevejo.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/74562319868.pdfIn PDF document text
    • http://www.depomatrial.com/file/raxuxulakibijek.pdfIn PDF document text
    • http://humansharehouse.com/userData/board/file/15593365430.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021090201151423.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7d4a46e63---16945408200.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=chrome+android+delete+search+historyPDF 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_off0000b65b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB65B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE6D 16164 bytes
SHA-256: fce19080f9197dc468738011ec8d9d87af5d24afa8304a169afc7bc0b619a922
font_02_sfnt_off0000f7f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F3 10780 bytes
SHA-256: 25eacb40111a39620dec3760b1feca7a2bad881e618887f97992997081c2ff6c