Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c765667dfe86130…

MALICIOUS

PDF

81.0 KB Created: 2021-09-17 14:46:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8179ea4d5121c857e7bc22741a92bb9d SHA-1: c63a27da7b5713543a4d29f04ec9815691f93646 SHA-256: 4c765667dfe86130239f08d04c58069808c8c583489bfdea669ce35e5630373e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with heuristics indicating embedded JavaScript and a link farm pointing to potentially compromised CMS uploads. The embedded JavaScript likely facilitates redirection or further payload delivery. The numerous external links, many hosted on disposable domains or compromised sites, suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://vinag7furniture.com/app/webroot/files/editor_upload/files/buvotunilowisasopebido.pdf In PDF document text
    • http://art-lan.ru/uploads/assets/file/90227201325.pdfIn PDF document text
    • http://dailitara.lt/bites/uploads/file/92254128890.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16136f10561a8f---kiniwozegiwutudenejov.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/sikifobotita.pdfIn PDF document text
    • http://rama-sp.com/rama/webroot/js/ckfinder/userfiles/files/76270192896.pdfIn PDF document text
    • http://thepokeluau.com/uploads/files/mosunilowa.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/rujotiwatabakenatogoma.pdfIn PDF document text
    • http://grafiport.com/userfiles/file/binopisevononimun.pdfIn PDF document text
    • http://brixtontaxi.com/survey/userfiles/files/89743334317.pdfIn PDF document text
    • https://cs168.tw/upfiles/editor/files/88917616265.pdfIn PDF document text
    • http://gemcom.org/userfiles/file/bajukesujezevu.pdfIn PDF document text
    • http://pointerboards.com/uploads/admin/files/vemomiwej.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139dc6a75055---8333292487.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161413f1cdbfb7---1130555148.pdfIn PDF document text
    • http://aedjtjdshbf.pretty-match.com/upload/files/43429156433.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/fegad.pdfIn PDF document text
    • http://teamhead.net/userfiles/file/fanixukebatuxaxenato.pdfIn PDF document text
    • https://agape4u.org/userfiles/file/84859396656.pdfIn PDF document text
    • https://tort-art.ru/userfiles/file/9887019199.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/48142777925.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=my+hero+academia+season+5+ep+2PDF link annotation
    • https://cakamuzejs.riga.lv/ckfinder/userfiles/files/24736821280.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_off0000ca90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA90 22196 bytes
SHA-256: d4a2f2b401c0872be433e6c63bcef6e8bfbb48fb3992e7860107982dfc226fac
font_01_sfnt_off000104a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A2 10996 bytes
SHA-256: b0f02a7b4706a5ca6595a2331e63597be878d55c18b8c4abe5d9be217dd6443f
font_02_sfnt_off00011e18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1