Malicious PDF — malware analysis report

Static analysis result for SHA-256 527fdb5b41a699c1…

MALICIOUS

PDF

75.1 KB Created: 2021-09-05 10:56:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 50e88fa8e7d770eadf75a3597843d12f SHA-1: d71be6f9bcb83f843c1a31d27f2506e535c9b2eb SHA-256: 527fdb5b41a699c1b39a74f3d5a0a099e6d710ffbf30e8f9d60bc9acb734460c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, indicating malicious intent. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution campaign. The presence of embedded URLs and the nature of the heuristics point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=social+skills+personal+space+worksheets PDF link annotation
    • https://pikhospital.com/ck_uploads/uploads/files/tasokoj.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16131ccfd2e614---vuvilewogaperepa.pdfIn PDF document text
    • http://biirbeh.mn/images/content/file/sirujavudo.pdfIn PDF document text
    • http://praxis-greve-polley.de/web/editor/files/zazudakilaxagukil.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7eaac05f9---bafavapefopi.pdfIn PDF document text
    • http://hodinovysoused.cz/upload/file/72078536771.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608f2e949c7fa---solexudavokepuvinife.pdfIn PDF document text
    • http://vstarmp.cn/upload/files/20210620_061237.pdfIn PDF document text
    • http://boletin.alicantehosteleria.com/lib/ckfinder/userfiles/files/tafifejazewo.pdfIn PDF document text
    • http://palestraarkadia.it/userfiles/files/2324935774.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/81569743215.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/f29846268ffb3df0e7866175ba6c0179/31535712852.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/9cb50a025cc2f08ba33a24386d0072a8/rexolowarasaxagow.pdfIn PDF document text
    • https://mmszke.hu/files/file/45575487092.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/5704228017.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/7414a4d48f4f8f4223a6c7293b5d6a29/40440190674.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/1dbe023eae038329adeac57b698d12dc/fepararan.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/dunogotisuben.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/23a22f2f85c1bf000a2e77bf692c19a2/dizejoj.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/41f401ccd7254dc317bf8f0b758e1d5c/dateguw.pdfIn PDF document text
    • https://salubrismd.com/wp-content/plugins/super-forms/uploads/php/files/9f9043fef06783cbb4896ad7ebf910e7/wuwefilixefofonire.pdfIn PDF document text
    • http://allseasonsbanquet.com/clients/868236/File/1867641505.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/9283c2c749f98250b57874f10bc0d2de/baredabelagufawazibukuw.pdfIn PDF document text
    • http://sdtrafficticketlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/paxafelukuwiworavajelok.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/6n64g8hd21adue60iaog02l20g/vutabitikiwolakuker.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/rixaropol.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/d65522be00b6d6a00fe2b985afbf6c80/dipakixu.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_off0000c2d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2D2 16996 bytes
SHA-256: 6a096ff8228135f99ca1a0f7d368d593686ff345e07775e704e8548ebab43a85
font_01_sfnt_off0000ee47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE47 10724 bytes
SHA-256: 64d07ffb193057739db13ace0dec09721d5e434b110ba636daec69a68bc7be45
font_02_sfnt_off000106e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1