Malicious PDF — malware analysis report

Static analysis result for SHA-256 ccb33c0c84ea1bd1…

MALICIOUS

PDF

76.8 KB Created: 2021-06-09 23:57:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 01815db00d411c0513c223b8ea714fb2 SHA-1: 28e2227e06179894e9c1281be8bfddd609282eaf SHA-256: ccb33c0c84ea1bd1a615dd853f2ebc151e0f4d4c2dcbe1b67e62528ca42e41a7
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to various domains, many of which are hosted on compromised WordPress sites, suggesting a link farm designed to distribute malicious content. The presence of a URL with the 'fake caller apk download' UTM term strongly indicates a phishing or malware distribution attempt. The ML classifier and ClamAV detection further confirm the malicious nature of this PDF.

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://medvor.ru/uplcv?utm_term=fake+caller+apk+download PDF link annotation
    • http://www.asslar.de/downloads/38317470404.pdfIn PDF document text
    • http://eksan-ltd.com/userfiles/file/binari.pdfIn PDF document text
    • http://baxsporthorses.com/userfiles/file/lefoselojovekujobure.pdfIn PDF document text
    • http://business-plan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/pigedinuzoziti.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/c887279dd8f07ba3dd0859d471d6a294/46923934435.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160aa8dad08482---vubafejase.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/3f62156c12d41d89b8e9e2ca05442caa/kuduxavazuxofubiroramob.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160750a28f2f58---33536540353.pdfIn PDF document text
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/f95a394573d97340579e6ecc01d03426/tobegimosenamozudat.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160781dfac1710---derejazeniboritexigu.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/c9e77d914d8b5cc33297e2aa29e8e9a0/fafivud.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/p99ou2fsjbut5b1hd1qvf9ljhn/poxumegofopuzife.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606caa83d3df2---52321766423.pdfIn PDF document text
    • https://charterfori.ir/basefile/charterforiir/files/sifapeva.pdfIn PDF document text
    • https://leganordavigliana.it/uploads/file/xizune.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_off0000eeb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB9 5000 bytes
SHA-256: 4521fb4408f7327d1a0f55c52b541de8c98167bd2e318983b08420f822c795b8
font_01_sfnt_off0000ffe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFE4 11744 bytes
SHA-256: 307489e184c21b94b8dc41f77f22310599a42fb99cbe7a2b222e2ffccdc6f8cd