Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef879124f88f6344…

MALICIOUS

PDF

96.6 KB Created: 2021-09-20 19:55:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 062bf00bec203df34ed4d5c1768f05ca SHA-1: 192a4c0a927695b48855608f7700199810e2a157 SHA-256: ef879124f88f6344a687b8a228d5f7cb8feea1fe667c14da3131028462fcfd4d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link T1059.007 JavaScript

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The primary purpose seems to be directing users to these external sites, likely for phishing or to download further malicious content. No scripts were extracted, but the structure suggests a malicious intent to leverage external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

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=5+major+biomes PDF link annotation
    • http://quick-thailand.com/images/uploads/file/68907781852.pdfIn PDF document text
    • http://theaterbuehne-schwandorf.de/userfiles/file/liluniwixego.pdfIn PDF document text
    • http://intertravel.hu/_user/file/64300986616.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aaf58e33aa---65484335141.pdfIn PDF document text
    • http://petra-dario.info/upload/datoteke/6445865836.pdfIn PDF document text
    • http://progettogeometra.it/userfiles/files/mezukurigasu.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142534f8f1ef---10214129539.pdfIn PDF document text
    • http://vansuloi.com/uploads/userfiles/file/14343980168.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/443397666a354c3bb35eb9aac8f7be6f/rudozo.pdfIn PDF document text
    • http://transbur.ru/admin/ckfinder/userfiles/files/11916492481.pdfIn PDF document text
    • http://veitali.com/upload/files/wuniwosifola.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b29a34915---6879730198.pdfIn PDF document text
    • https://konyaalotaksi.com/userfiles/file/bikagamejosesunurumenija.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16140cf63d895d---xamaketo.pdfIn PDF document text
    • http://irinabailey.com/upload/files/59091210563.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613db97501865---73951217579.pdfIn PDF document text
    • https://xn--80aesyq.xn--p1ai/files/file/84246932034.pdfIn PDF document text
    • http://carrasvilla.es/uploads/files/56455126142.pdfIn PDF document text
    • https://phukienbep.net/media/files/benevokuxuvigujetaf.pdfIn PDF document text
    • http://longruiglass.com/ckfinder/userfiles/files/20210911_233029.pdfIn PDF document text
    • http://masterkontroll.hu/ckfinder/userfiles/files/resut.pdfIn PDF document text
    • https://nbc.com.vn/ckfinder/userfiles/files/3730075868.pdfIn PDF document text
    • http://gzafjc.com/uploadfile/files/kabolal.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/zewiledatexevuru.pdfIn PDF document text
    • https://autotoner123.com/home/autotone/public_html/ckeditortest_WORKING/ckfinder/userfiles/files/23782762757.pdfIn PDF document text
    • https://ratodua.com/contents/files/31513898146.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_off000117d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D8 17680 bytes
SHA-256: 5c33a099d1ced95136145d6b521dbc83bc5dee86100bcd5df72b0a05b671affa
font_01_sfnt_off00014576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14576 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015d8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D8D 10328 bytes
SHA-256: 49cc26d1b00a8a5292faf8714036162d64022a91edcb272c7c3c3935b4cc36c1