Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a376b9f05caaff5…

MALICIOUS

PDF

83.5 KB Created: 2021-09-24 11:02:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0b67605a7ee6f00b579b7075de50f82b SHA-1: 458854d960355659b710013fe6a0984c17a184b0 SHA-256: 4a376b9f05caaff530d4adf8f0511691360ac63c00a40f7b4b9dcda12f1b659f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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, with many URLs pointing to compromised CMS uploads or disposable hosting. The primary purpose appears to be directing users to external, potentially malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://drafthe.ru/uplcv?utm_term=night+mode+chromebook PDF link annotation
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/d8ff6839899a9e9cb8592b3e73779445/diwaduwusaxololawazafilo.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210903_9F8F77E51F4B33E6.pdfIn PDF document text
    • http://mcenterdk.ru/fck_editor_files/files/40765510078.pdfIn PDF document text
    • http://wingmanresearch.com/userfiles/files/7692276505.pdfIn PDF document text
    • http://konemara.hu/userfiles/file/sijevokokelesumovilod.pdfIn PDF document text
    • http://vsrru.ru/userfiles/file/49049486698.pdfIn PDF document text
    • http://career-id.org/ckfinder/userfiles/files/dewukosodolupubusaraxuke.pdfIn PDF document text
    • https://fotobolfestmeny.hu/mvc/userfiles/file/18353348140.pdfIn PDF document text
    • http://xn--djr00fsyfv0o5qgy9u.com/filespath/files/20210907200018.pdfIn PDF document text
    • https://izr.fr/files/18194465263.pdfIn PDF document text
    • http://mesterteto.hu/userfiles/file/44590209834.pdfIn PDF document text
    • http://sergeybazarov.ru/file/nobufesarid.pdfIn PDF document text
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/15210647555.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/e5ed664569e49db239e6d2ea06abefa3/26875841292.pdfIn PDF document text
    • https://hbfilm.ca/resimler/files/sagowixoleniduxope.pdfIn PDF document text
    • http://dcbestwings.com/uploads/files/vanelor.pdfIn PDF document text
    • http://istvietnam.com/rich_editor/file/foduwujolowerilamogomu.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/6f1034bf0833490758a0ae879b20295a/wikip.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/5351009303.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/zarelutijavem.pdfIn PDF document text
    • http://umhouses.com/uploads/files/nuvex.pdfIn PDF document text
    • https://immo-macedo.lu/userfiles/files/48989950229.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/dewenej.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_off0000e020.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE020 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f837.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF837 10544 bytes
SHA-256: 8503226803e52cdd2d976b967d0d37eb227f21694d5e40942321163c78f31bc1
font_02_sfnt_off00010ffc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FFC 18696 bytes
SHA-256: 17b3a754ed767c72881a8996f26b4eba4971a1af6b822643792b853788e66d95