Malicious PDF — malware analysis report

Static analysis result for SHA-256 9543eec8e6d49d58…

MALICIOUS

PDF

70.4 KB Created: 2021-10-03 20:16:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e6e92cf78b41d95be70ac16bd3493bdb SHA-1: a3a984e17a389e4cbd4d82b2c5b52369a715764b SHA-256: 9543eec8e6d49d587181c2326510d4b9e1d169baf260f3a0adf3f24a1ec4d354
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or are part of a link farm on disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the primary attack vector appears to be directing users to malicious websites via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://nomylo.ru/uplcv?utm_term=preaching+the+word+commentary+pdf PDF link annotation
    • http://chernogolovka.inhome360.ru/admin/ckfinder/userfiles/files/37337208464.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/mujowutasowadulosenawu.pdfIn PDF document text
    • http://ets-sptk.ru/pic/file/48745301731.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/vozaxoxivunovezapub.pdfIn PDF document text
    • https://oreopay58.com/ckfinder/userfiles/files/lebisenoreribomiw.pdfIn PDF document text
    • http://phunggia.biz/userfiles/file/41933759367.pdfIn PDF document text
    • http://hertzlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/12678767352.pdfIn PDF document text
    • https://slavicchurchmississauga.com/fck_upload/file/88543259732.pdfIn PDF document text
    • http://mn-print.ru/ckfinder/userfiles/files/24058588813.pdfIn PDF document text
    • https://ladulceseguros.ar/noticias/fckeditor/file/9097621554.pdfIn PDF document text
    • http://getsolarnj.com/userfiles/file/67733162260.pdfIn PDF document text
    • https://www.vignolaweb.it/ckfinder/userfiles/files/9545800629.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/19772512806.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/bigovemunupirilonexejif.pdfIn PDF document text
    • http://ms-domino.eu/images/file/files/jalivaralirosovijaf.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/16137b653cc356---batuvexi.pdfIn PDF document text
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/nekubotinerijege.pdfIn PDF document text
    • http://gotween.com/userfiles/file///75158174502.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/k8g8ebcr6f7qnpb8uhvtbrdvka/folopumipofu.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/29902977567.pdfIn PDF document text
    • http://akgwealthplanner.com/crm/files/5857224649.pdfIn PDF document text
    • https://superpackeg.com/userfiles/file/59790235332.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/16159d4cc605ca---52698070675.pdfIn PDF document text
    • https://e-fasteners.eu/media/file/59998341151.pdfIn PDF document text
    • http://vako.vn/app/webroot/uploads/files/megediralivofevotoxivifu.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_off0000b118.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB118 16144 bytes
SHA-256: 8028cfa86d8b45545aff341af04d0661bd7eb512e5a1f7f2580214c85c0d9cf5
font_01_sfnt_off0000da80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA80 11052 bytes
SHA-256: ba640783f8c69ef817627409a97f6d10c4e8832221e4fcc013e605c15b9e215e
font_02_sfnt_off0000f3f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1