Malicious PDF — malware analysis report

Static analysis result for SHA-256 98c0277f2509ad58…

MALICIOUS

PDF

68.8 KB Created: 2021-06-13 20:58:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0f662b53af2f7335909fe3ce5da85d3f SHA-1: 7ea1e0dbfa2ded56f7f4f7e9953f5c1e8bec11a7 SHA-256: 98c0277f2509ad583a0720e7f244dbbeb4e8f2faab93fed10812fb9395fa2738
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external resources, many hosted on compromised WordPress sites and disposable domains, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to deliver a phishing or malware payload. No scripts were extracted, but the overall structure points to a social engineering attack leveraging external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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=gate+previous+papers+with+solutions+for+eee
    • http://hifi-markt.org/kunden/kronhardt/ckfinder/userfiles/files/40775775338.pdf
    • http://videofilm-tv.ru/content/File/71949596030.pdf
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16073524d9dd78---fimitevizefiraxe.pdf
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/6918d846b779d1f88d610422b852c8fc/60026662260.pdf
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160aca687d8e27---manuzefarawutowef.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b2fb80ec114---gegawerusaxugonuseb.pdf
    • http://archi1919.com/smlclub-files/file/vawimonaxafir.pdf
    • https://blindnow.com/userfiles/file/88696999580.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073ba0ce01b1---kuwigawezomibelod.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/674bf590d55afd4fc1a02a475dd2e358/sesizutezoxetupoma.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/4b358cg02vade4nf9c7llhp2g6/29384718356.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608fab3183f1f---54039860643.pdf
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094cbb52d884---numezolajepepinumuzufe.pdf
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/aalrjom5ij211j55qomc2gp2mb/sowidowo.pdf
    • http://alarcon-v.com/editor_upload_image/file/48275646126.pdf
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/7e9c8fa6b371c72a72abaf340b387ee8/pisapimulixubuga.pdf
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/d2ae32215e50c9487a5e20fe11d3d9d3/maziwit.pdf
    • http://krevue.cz/UserFiles/File/21527813047.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cd12.bin
77e41457073dc3f84761dc2575c50e208f3f2fa121a122c320de73da7581be36
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD12 5172 bytes
font_01_sfnt_off0000dec0.bin
9e18247431c9888ca91cf23328ab3cc60e41d62f51abe99df08f2ce10e496495
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEC0 11004 bytes