Malicious PDF — malware analysis report

Static analysis result for SHA-256 f258a6d83dee43a0…

MALICIOUS

PDF

75.4 KB Created: 2021-05-22 22:10:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: e5632eed79eadb80c9b40be75ab42c6f SHA-1: 07b3a4e5f2d9284dd6802c4e6fa2db768bd87d0e SHA-256: f258a6d83dee43a0b9212f50d18c259af91d0222c4cc81ee2ea25a8042673166
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to external websites, many hosted on compromised WordPress installations, suggesting a link farm designed to redirect users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://irlanc.ru/uplcv?utm_term=paragraf+%25C3%25A7%25C4%25B1km%25C4%25B1%25C5%259F+sorular+pdf+8.s%25C4%25B1n%25C4%25B1f PDF link annotation
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16090f508bb087---92173964156.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/825dc46b50514be65d7e6005bf855b78/xojutakowapuze.pdfIn PDF document text
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/95a2b1f8edf07a4cbde251919fc2d8cf/35217670364.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608707d69a5f3---fufovusudepigegusasepugub.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/f016781d47e77c15a30c60bad2b9f731/petezubujitewovagu.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/745rsd92as9niggqs74qnngif5/nujenizurubates.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085727aab7e7---mebibi.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/172b59277069360534fbb834ce00ec2a/fasuzivexomusimeres.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/jc87rj8q86oidn7sg0ilaisj8n/vakasofoba.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160832e7005d23---75325423477.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb27115baf---95714820661.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608960ba3908b---momamu.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095c14852e71---pavuxufitugalilife.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e571.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE571 6112 bytes
SHA-256: 2e7fba0983557c6ae691c70c935bad791797fd55c15440897e63dc1f7a8b2458
font_01_sfnt_off0000f990.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF990 12088 bytes
SHA-256: 8b0bea1bb33eb8cf80e596ffa92431bb683a7b8b9c926c5c19b62e0b73db59b8