Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d75b5ce7b81d508…

MALICIOUS

PDF

72.7 KB Created: 2021-09-08 20:37:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6688d87ab77b9de02a124f13b1d0d535 SHA-1: ead278b85de081194ef76b93a83aee223ddc892d SHA-256: 6d75b5ce7b81d508cfff0789be63b64cf3632e882c2d5910b486146fae0a6e7b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed for SEO manipulation and user redirection. No scripts were extracted, but the presence of multiple external links indicates an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://zd-zeta.com/uploads/files/202109071603347550.pdf In PDF document text
    • https://hometeamcorp.com/images/usr/98681277454.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/34643070206.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/bdf503380ff3434338e8cb5ecf09da52/56260831589.pdfIn PDF document text
    • http://tscyw.net/userfiles/file/20210901060253_9g51to.pdfIn PDF document text
    • http://world-housing.jp/ckfinder/userfiles/files/12909439384.pdfIn PDF document text
    • https://szemvidito.hu/sfwkr/feltoltesek/Images/Image/95408990481.pdfIn PDF document text
    • http://studioiulianella.it/userfiles/files/23390495488.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/96625762841.pdfIn PDF document text
    • https://ijacr.net/assets_admin/ckfinder/core/connector/php/uploads/files/pesetepozukeseli.pdfIn PDF document text
    • http://arc-en-cielproduce.com/ckfinder/userfiles/files/kisadopirexififojo.pdfIn PDF document text
    • https://catbasailing.com/upload/fck/file/59321506485.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/jisawatiruleruzakamitin.pdfIn PDF document text
    • https://gonguyenkhoi.vn/upload/files/23403236644.pdfIn PDF document text
    • http://digitalpolicycouncil.org/imagenes/file/jizuvijugizepi.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/16132d0f78de39---47702074857.pdfIn PDF document text
    • http://mashhadgardi724.ir/basefile/mashhadgardi724/files/45414959103.pdfIn PDF document text
    • http://kirilmazbardak.com/userfiles/file/6576504474.pdfIn PDF document text
    • http://anshan56.cn/userfiles/file/16305844621970637385.pdfIn PDF document text
    • http://mbeautyconcept.com/upload/content_images/file/79220388515.pdfIn PDF document text
    • https://konteshamamotu.com/userfiles/file/nudanunoganero.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/161353ac929c1a---dipemafulinipu.pdfIn PDF document text
    • https://b2bircruise.travflex.com/bot/ckfinder/uf/files/21634968561.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=thunderhead+neal+shusterman+pdf+espa%C3%B1olPDF link annotation
    • 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_off0000b82a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB82A 10940 bytes
SHA-256: a0628aaf99e875bfae2599caa11a6aa4b8c41d1617af60882264d80f21848eb5
font_01_sfnt_off0000d109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD109 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e91b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE91B 16428 bytes
SHA-256: 927def8df9af53584fc25d388a08ed47a5a1efc6b8245f30b1dd9560d3d48db2