Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f8544be9408bc22…

MALICIOUS

PDF

78.8 KB Created: 2021-07-06 21:58:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 022708827a6bf2dc4cc9297143dd393b SHA-1: 58a22e31a8bef4b68b36a881f0840da9912f6ee3 SHA-256: 1f8544be9408bc22d0642d066c21893f1925c661937b5099693fea5527921240
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress upload sites and other disposable hosting domains. The embedded URLs likely serve to distribute further malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a09399bac0d---vakagimixesokepizelijuwu.pdf In PDF document text
    • http://dush-kz.ru/uploads/fck/file/15573284191.pdfIn PDF document text
    • http://cokhibaosang.com/media/ftp/file/59822727574.pdfIn PDF document text
    • https://vinadesigndanang.vn/uploads/image/files/9781316724.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160daa9af217cd---bupudezudomajorul.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/g56l522ubt659avk5in9j7gq4m/nugotu.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/58d17b99bd43d0899cbad2aaa6be1a9a/59338096165.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/bbb66ed46e05c81aaba0d8a1f1261ad9/bitajaxuredafinaf.pdfIn PDF document text
    • http://vdadanang.vn/app/webroot/assets/files/luwafujexadawujoxu.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ae408c0be5---13926257868.pdfIn PDF document text
    • https://nepalmicrofinancesummit.org/userfiles/files/53349828267.pdfIn PDF document text
    • http://desushibar.com/userfiles/file/86295688890.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d02a625beb4---bofagowotibo.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/6e1eb3ab26bebca9a79b98e927986718/32407211290.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/79159094752.pdfIn PDF document text
    • http://el-master.ru/userfiles/file/pupojiwavimokazibodimif.pdfIn PDF document text
    • http://pierrevillers.fr/mairie_files/file/98963803568.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/931f68b95950d03986460938f59e6b21/88377389017.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082bf4c4aedb---laxokisusadezutazusebip.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/f6cc875c0530abdfdf7d581c4bb4ad9d/removitigig.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/20104566160.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160ab7543c8e8e---15731444885.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609aa8f7c8cb5---rakoropuguzorolisizejune.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=the+tom+and+jerry+show+season+2PDF 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_off0000d0dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e8ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8EE 16892 bytes
SHA-256: 1265482dc2ddc0436f4d55cb5172ecf1663b75aa6d2ae3782d1965b641f53e69
font_02_sfnt_off000114df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114DF 10788 bytes
SHA-256: c4a5ca3b54fcbc73a5eeb3001da89ef2a4ae2e23435605dccf72d15d603fd308