Malicious PDF — malware analysis report

Static analysis result for SHA-256 a670be42ea9b4917…

MALICIOUS

PDF

88.6 KB Created: 2021-08-11 05:55:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 7ec6527428183fcd784c6c15235cfd25 SHA-1: 1139a108d4beece5e0e7bb42cc09976d41ab6e14 SHA-256: a670be42ea9b4917c32d8ca9cf2c4497df649e8c5d59881416b2de1bbe2349cc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript and a significant number of external URLs. The heuristics indicate that this PDF is acting as a link farm, with many distinct hosts and links, likely intended to redirect users to malicious content or phishing sites. The embedded JavaScript, though not fully analyzed due to obfuscation, is a common technique for initiating malicious actions within PDFs. ClamAV detection further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://infrive.ru/uplcv?utm_term=how+to+draw+a+superhero+mask+step+by+step PDF link annotation
    • http://brunsfamilyreunion.org/clients/e/e7/e70b0594429ddd28dfd4dd2f61c76e80/File/zezip.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088a976870ef---50305156525.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608521bc708b5---jizijawowex.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/08684ac9d009f6130540ea0afcef2ed9/69061889369.pdfIn PDF document text
    • http://nollve.com/img/editor/image/file/49386327683.pdfIn PDF document text
    • https://fwullong.com/upfiles/editor/files/43969838498.pdfIn PDF document text
    • http://smithmaloney.com/clients/3/32/32eae1a42220421eddab78da2f55685d/File/fakupamixivim.pdfIn PDF document text
    • https://chatsystem.site/js/ckfinder/userfiles/files/13653632461.pdfIn PDF document text
    • http://ruresept.ru/files/file/6954537514.pdfIn PDF document text
    • http://accronline.com/userfiles/file/figof.pdfIn PDF document text
    • http://promador.pl/userfiles/file/26402606863.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/xewog.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/9d27e82d2818d426829112f23fc40e5f/riwodezurik.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/51b968c7a5328d7334470b5ddf14ea20/1349264245.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b3f123f281---56347841549.pdfIn PDF document text
    • http://protok.pro/upload/files/42371427939.pdfIn PDF document text
    • http://radio-salsa.com/php/rs/filesupload/file/kexawipofesedabupit.pdfIn PDF document text
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/ce5079ef04e279b3338427582aa94c4b/nisudajuvopolekukole.pdfIn PDF document text
    • http://imi.vc/upload/files/82798089287.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bbed45ddc70---wuzizobuw.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160f98dce83dea---9263213307.pdfIn PDF document text
    • http://szzxwx.com/Upload/Upload/file/2021618214366847.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/89289879980.pdfIn PDF document text
    • https://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/f471680dffd36a2b08a86a24b16ab4d0/89472662025.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_off0000f6c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C4 17092 bytes
SHA-256: c75d20798d77e8deae6f72a39b5f9026920bab948baf65dc8075a5b9652e415e
font_01_sfnt_off0001239a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1239A 10940 bytes
SHA-256: 737ba97ece94552c3b8e745a0b6360f33e3fbc6d7c2afeb45719b516f6df8962
font_02_sfnt_off00013cce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1