Malicious PDF — malware analysis report

Static analysis result for SHA-256 1e8f1b524dd447a5…

MALICIOUS

PDF

74.7 KB Created: 2021-09-17 00:35:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f0332b7badf5f167f223aa3aaeda7ed1 SHA-1: feb104df43d65030e7ce21beb3c5d96dd2b7dacc SHA-256: 1e8f1b524dd447a526cddd912acd8fd25cc61084bd7910b341bd091f759d226a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document flagged as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of embedded URLs and the nature of the heuristics suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://pistant.ru/uplcv?utm_term=harry+potter+movie+1+free PDF link annotation
    • http://quinta.cl/upload/files/kifeveranemoxe.pdfIn PDF document text
    • http://cerrutistudio.eu/userfiles/files/kujekivukizonowonivugo.pdfIn PDF document text
    • http://thomas-zigon.de/images/file/wijukos.pdfIn PDF document text
    • http://bilmatbasim.com/userfiles/file/dadoza.pdfIn PDF document text
    • https://observatoire-omic.org/documents/file/20528916210.pdfIn PDF document text
    • http://hanabi-la.com/uploads/files/zibigeziju.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613beec8043d1---63948414229.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/40426866657.pdfIn PDF document text
    • http://yibetter.com/data/files/49881103515.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/dopaxuvifefototopenu.pdfIn PDF document text
    • http://hzbmsj.com/images/upload/File/jitod.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/ac55dhroimcpd1h5plnms1ieo6/nasat.pdfIn PDF document text
    • http://www.darvidproperty.com/news/file/xidesibatun.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136783d66efb---garawuvuletemopasutofuriv.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16132b5799fe59---30025396201.pdfIn PDF document text
    • http://btfa.tw/upload/files/48663528895.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/kufedelagisa.pdfIn PDF document text
    • http://hoanggiaphatland.com/uploads/image/files/diwemefovodewemipuku.pdfIn PDF document text
    • http://podhoru.cz/userfiles/file/zitamumuwawis.pdfIn PDF document text
    • http://pedraferro.com/files/files/xajifexanide.pdfIn PDF document text
    • http://bulmarconsult.com/files/xozedinujisuma.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/21324204874.pdfIn PDF document text
    • https://commonlawhouse.in/userfiles/file/99750607752.pdfIn PDF document text
    • http://tecniagua.es/uploads/ckfinder/files/70548955339.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_off0000bf86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF86 10424 bytes
SHA-256: 312c23ea4ec1f46b377cd9ca2b70d9a05ec012527828c2e8d3ef84107177e250
font_01_sfnt_off0000d73b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD73B 17568 bytes
SHA-256: 92aebf38812ca098fb0e0a7084c636722f796d67a7e9dff46688e6690fe453a8
font_02_sfnt_off000104d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1