Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a6d04e0eae392ce…

MALICIOUS

PDF

77.6 KB Created: 2021-09-10 07:19:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 277ba0c1c2ef3c19bf8cc51dc1a5eec6 SHA-1: b3dabc503c39ed83fc7e2da9bb9049ce27e3d5b0 SHA-256: 4a6d04e0eae392ce6d6677e3926ab4f293b03dc3a813b1de59a2cad5a934ce9c
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, exhibiting characteristics of a link farm. Multiple heuristics indicate the presence of external URIs and links pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body is unreadable, but the heuristics strongly suggest the PDF's purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://coretry.ru/uplcv?utm_term=battle+warships+naval+empire+mod+apk PDF link annotation
    • http://brno-skoleni.cz/ckfinder/userfiles/files/5656055242.pdfIn PDF document text
    • http://autobedrijvenindex.nl/images/uploads/28202177753.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393dae10fbf---6662553911.pdfIn PDF document text
    • https://aukshanya.promosing.com/alpha/ckfinder/userfiles/files/29289562031.pdfIn PDF document text
    • http://4grd.com/cmsimages/file/20888824643.pdfIn PDF document text
    • https://gancza-yacht.pl/userfiles/file/9986435301.pdfIn PDF document text
    • http://wojno-stal.pl/pliki/file/82580300634.pdfIn PDF document text
    • http://changjiujz.com/uploads/files/202109042107562064.pdfIn PDF document text
    • https://zoldlepes.hu/userfiles/file/8984470561.pdfIn PDF document text
    • http://tayles.com/uploaded/77469775032.pdfIn PDF document text
    • http://vekosgroup.ru/userfiles/file/taxef.pdfIn PDF document text
    • http://numere-mopede.ro/mm/file/57662303924.pdfIn PDF document text
    • http://alatasfilms.gr/ILC/img/file/leluzevafa.pdfIn PDF document text
    • https://cevhertemizlik.com/userfiles/files/kuwob.pdfIn PDF document text
    • http://hzqzg.com/d/files/wajolixora.pdfIn PDF document text
    • https://malayalamfoundation.org/admin/my_files/file/27415136895.pdfIn PDF document text
    • https://cepatdaftargroup2.com/contents/files/moxipajugepe.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/uvu6u1au2ndfc5l5vd82reg6t1/femurimuwuvel.pdfIn PDF document text
    • https://clickbox.ro/images/file/13943142312.pdfIn PDF document text
    • https://lockerova.eu/admin/upload/documents/77276716624.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137bcbd2a980---70637261588.pdfIn PDF document text
    • http://azco.friend-match.com/upload/files/33892065548.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_off0000c183.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC183 20316 bytes
SHA-256: 0fb16d2d181c835a78b89fd87d4d211c40fd76f97bc80035709a5968ae996495
font_01_sfnt_off0000f714.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF714 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F2B 10952 bytes
SHA-256: e5a428605dbd7054ffc4bf878e2822ec642b9b9f5842be09f0e1de7ac0a8ab3c