Malicious PDF — malware analysis report

Static analysis result for SHA-256 217c2b7dabab7e0e…

MALICIOUS

PDF

87.3 KB Created: 2021-09-14 07:48:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: faa4a1b84753948c8858a8ba2f123559 SHA-1: ca2ec5e719c99d2f36a44a91de87dd7ceb13faaa SHA-256: 217c2b7dabab7e0e50e9ddc054c80bc539ad21aa18fd4af4a6fe756b8b8c041b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting it's used to distribute further malicious content or phish users. The embedded URLs, such as https://inwebjor.ru/uplcv?utm_term=limitless+book+pdf+free+download, are likely part of this distribution network.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://inwebjor.ru/uplcv?utm_term=limitless+book+pdf+free+download PDF link annotation
    • https://bursakaynak.com/userfiles/file/26929346593.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/sabis.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe74c5eef8---36379765659.pdfIn PDF document text
    • https://greenline.bg/userfiles/file/bupunugomasununu.pdfIn PDF document text
    • https://sokolzgierz.pl/web/uploads/files/77718174260.pdfIn PDF document text
    • http://daejonggyoyc.com/userfiles/file/20210914084503.pdfIn PDF document text
    • https://marupyara.com/fotos/userfiles/file/sekaworutukekel.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/654321f167ca4bb957a0691ad642134d/lamagek.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/16136b9b7a2ec7---rukekikegirune.pdfIn PDF document text
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/tipenojojazuv.pdfIn PDF document text
    • https://sfeerweter.nl/userfiles/files/67979083350.pdfIn PDF document text
    • http://wimborst-ceramics.nl/ckeditor/ckfinder/userfiles/files/kilanerobifet.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/91452307718.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/nopugubuxujafaziforewired.pdfIn PDF document text
    • https://servicepapik.ro/files/fibanemij.pdfIn PDF document text
    • http://silesiacapital.eu/data/file/dumame.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/pofodemokazif.pdfIn PDF document text
    • http://www.biogreeno.com/cms/ckfinder/userfiles/files/13148167557.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/2798926c62569c9c5d07d7846bbe077a/noxabasa.pdfIn PDF document text
    • https://mallncart.com/userfiles/files/11618059229.pdfIn PDF document text
    • https://iqmuseum.mn/uploads/files/jagesejojufa.pdfIn PDF document text
    • http://twilaw.com/files/files/vajimefu.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_off0000ef8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8C 18120 bytes
SHA-256: 032528904f9f1b12de0770f47c3f6659882eb2bd57fc4ef7ea1f5d78b12cb398
font_01_sfnt_off00011e82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E82 10932 bytes
SHA-256: ca4363915146e4bff541df029bb3b24ca109ac300f1892f4ed05c5b7e9d11ab7
font_02_sfnt_off000137aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1