Malicious PDF — malware analysis report

Static analysis result for SHA-256 57944319d9bec69d…

MALICIOUS

PDF

73.4 KB Created: 2021-09-01 03:38:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4b747b6a12cb8d922a459e87ac2346ff SHA-1: df78c93fb70b528e6b19a898b6ab09e3bc23c332 SHA-256: 57944319d9bec69d64fad80d9d8ad3c76ecda75b5cae2eba6c2859fea3894780
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many of which point to compromised WordPress upload directories, indicating a potential phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable, but the heuristics and numerous URLs confirm the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://gibisch.org/files/files/48065055991.pdf In PDF document text
    • http://sushikyototogo.com/uploads/files/fikujekewusosa.pdfIn PDF document text
    • http://smeclassof1987reunion.com/clients/37165/File/ralawipojowobigumigawi.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/42kolubv906p4fghses2i88g55/puduteru.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/8l9q0vh2jaghuchrle0cl303uj/97052538107.pdfIn PDF document text
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/4053637725cd6939eb3c19ae9b33e40b/xojebekim.pdfIn PDF document text
    • https://rafautama.com/uploads/file/55695048122.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/20316606306.pdfIn PDF document text
    • http://thietbianninh188.com/uploads/files/23231229792.pdfIn PDF document text
    • https://alteanetworks.fr/img/file/moxodagefotofuwulavaviwen.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/files/neladepe.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16093e6943dd16---36248014743.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609164a9e7699---80011924728.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb9bbbccde---91068922674.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/40566869157.pdfIn PDF document text
    • https://samsunyapi.com/userfiles/files/lutinak.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ab8f28992bd---puzeliloji.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/65f37eb7691744822a65d4f030b63cb1/mofoligaxozajadixadakub.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608526a0d5d60---vopabisekofozibus.pdfIn PDF document text
    • http://www.heksan.com.pl/file/nufigexoniwagokosaj.pdfIn PDF document text
    • http://caythuocdangian.net/images/files/70594523256.pdfIn PDF document text
    • https://drakbera.com/ckeditor/ckfinder/userfiles/files/41168759147.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074887ba1e9a---jemage.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/31297384611.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/e0410c7331dff062dae19ad59ef78361/36766167791.pdfIn PDF document text
    • http://kentcliffordreunion.com/clients/a/aa/aa84b18e55fac3ff3c25336c5005d9e5/File/1207063478.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=noticed+lil+mosey+gayPDF 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_off0000bce5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCE5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d4f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4F7 16436 bytes
SHA-256: c044de7e048f28401f2f3ea5d80b9789b96acc23506236f20b0698e3b8cd26b3
font_02_sfnt_off0000ffab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFAB 10600 bytes
SHA-256: 2ee5da29274f5e57e4bc01b231214a5c735a51dc8190c10ee0a3d338f0a5a60e