Malicious PDF — malware analysis report

Static analysis result for SHA-256 73fded1c6bc62cc6…

MALICIOUS

PDF

88.5 KB Created: 2021-09-07 16:51:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 819b50d7ecec402de2d569292bbc62af SHA-1: 7bf65a814b5b4a89650f8e0a7f6c6606221b3463 SHA-256: 73fded1c6bc62cc659f53b5442fcc2d7f436cda2d78b686bb83dc85860edd49c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm pointing to compromised websites, with a high ML score and ClamAV detection confirming maliciousness. The presence of external URIs and links to compromised CMS uploads suggests a phishing or malware distribution attempt. No scripts were extracted, but the PDF structure itself is indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/a7486b272a68ba362d1ecd482c620ab8/50738190601.pdf
    • http://sdes.in/uploads/90320047984.pdf
    • http://indianmailbox.com/assets/images/userfiles/files/zikumewerexasoxisi.pdf
    • http://gurukripapublicschool.com/userfiles/file/xasisa.pdf
    • https://stpeterscbs.ca/ckfinder/userfiles/files/26435916782.pdf
    • http://netflor.pl/upload/File/pevufitobexesidodore.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/37860b51ce4e5120135af2fc98b0b7c4/noduxam.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/6c24b4bd6da1edb08fe12c4b7ae34f07/judomijivunotesomevenudaz.pdf
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/26jhmkqkvcn34m3k2hbhkr6o2n/31885916406.pdf
    • http://uco-kampen.com/media/files/dusixapudubivegu.pdf
    • http://claudiamelchior.it/images/file/30542619127.pdf
    • http://sllight.ru/design/img/upload/file/84269026529.pdf
    • http://kapelski.pl/userfiles/file/tunowago.pdf
    • http://orchid-daikanyama.com/userfiles/file/rawenimev.pdf
    • http://e-pisanie-prac.pl/famprojekt_z_serwera/images/file/bojipazukimuvajavobisaz.pdf
    • http://cn-junsheng.com/upload/file///202162053078898.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bd7b10df43a---daxupazif.pdf
    • http://macabrey-luthier.fr/data/Files/dabedozijemifiw.pdf
    • http://sobateracota.ro/mm/file/tumabu.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089d31572c23---semetevopazeno.pdf
    • https://kimtuong.vn/isc/public/files/fckupload/file/lofatukeladibofotiresav.pdf
    • https://alate.org/admin/fckeditor/editorfile/30673835924.pdf
    • http://z500.si/files/piwemuferetelozogij.pdf
    • https://castilloexterior.net/ckfinder/userfiles/files/bamoguvadokuzedirogatiz.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/6ec60af0c947adb4c7fddcc324691e16/24748471227.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/e151ab387d4d152b7eafdbf2ced0228e/33507019394.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=plasticidad+mecanica+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f543.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF543 16792 bytes
font_01_sfnt_off00010d55.bin
59faead3dabd355be81d708ef3ba783f06e7ffad43ef27f930cd9797a5bad704
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D55 18048 bytes
font_02_sfnt_off00013ca0.bin
f5145dae464ff8a34f094e3c8fb7f075161a1f527197980d9b0b210c5daf13c8
pdf-font-stream PDF embedded font (sfnt) at offset 0x13CA0 10560 bytes