Malicious PDF — malware analysis report

Static analysis result for SHA-256 a096d03609eba97a…

MALICIOUS

PDF

87.0 KB Created: 2021-06-13 07:16:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 12f8c1387abadb46a759939dc1f0ecae SHA-1: 3bb2fd53a7925f725645729ab0149c8533c1307a SHA-256: a096d03609eba97aa63a5ef90a3061b044874884ac24f2d8fafa1ee1655326a5
96 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories, indicating a link farm designed to host malicious files. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's part of a phishing campaign, likely using a spearphishing attachment as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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=neet+biology+question+paper+2020 PDF link annotation
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2632ef5c0---tujovesojufolewibemol.pdfIn PDF document text
    • https://zionapostolicministries.org/uploads/file/wuwabevujabotuwujejap.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/casicfjq1vp2q5dm0pfltjjb82/2787890314.pdfIn PDF document text
    • https://www.swissfillon.com/wp-content/plugins/super-forms/uploads/php/files/38ad52393bfa9e96576a7439fb1d16db/jusofi.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/4d59ac1e1f302214a50a97ce200102cc/boruwunezuner.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16074d57a8abb6---fejibugutibef.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/bubagabeb.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9ba5593e49---10005803948.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/cb23fd0529b9ddc3c908afc73ae08cbb/ridupamujoribosewijivida.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/6282b6b489fae9017137599e4b8661ac/medifebotifonewosokoba.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/jibunaraven.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/365o5bnsdlc5j4vii4sh6rpsn5/tizasoj.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/a092a2f9fabf5791d307bac5f9356025/38560611358.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8cfd6b64d4---34810316488.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16083338825a53---82540036336.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/8cb496fadfe906d7bb3e020a37f5bf76/nenuxuvatekidezirav.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010714.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10714 5480 bytes
SHA-256: 1b4bfecd6181276709416e892228bc0e5d5efdf0d5e3a7e6c39bcbd42500c632
font_01_sfnt_off000119c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119C2 11000 bytes
SHA-256: 495f89208783cd74e97f85b79bfd2dd4f0db86cc83b055a1754f7452491c3e7a
font_02_sfnt_off00013f31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F31 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378