Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad9c4d95240ad555…

MALICIOUS

PDF

83.1 KB Created: 2021-08-13 17:13:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: ed8164deccca19ea672038a0743c6524 SHA-1: 99e8b5d35e26340cb53d5f8f24548d4202499c9e SHA-256: ad9c4d95240ad555883d823064ec47b7c52c6c51cd7340226d0a2e42a072f78c
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised or disposable hosting domains, indicating a link farm designed to redirect users. Heuristic firings like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly support this assessment. The ML classifier and ClamAV detection further confirm the malicious nature of the file, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/713430931e3523b92d55daf41e609657/47170732430.pdf In PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091c8d7a17f1---55270302632.pdfIn PDF document text
    • http://jubileejec.com/userfiles/files/fafafisezukok.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/24973641792.pdfIn PDF document text
    • https://lawweb.info/mycms/admin/userfiles/file/pogomolole.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/5d38809efd4a828155ee37cb317403fa/berumiras.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/lelijuvuzamadob.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ec4aaf923c1---2169496735.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf86f9ead80---29949377497.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bffbbe3606a---wivomatavawufe.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a65b969ddc0---56785157562.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/lasanamazadasanitejeva.pdfIn PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/bonutakuxozaxel.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/6a6308578fd238c805f4b2e300cf70b5/xaseb.pdfIn PDF document text
    • http://geose.ru/userfiles/file/fegivekasapetutepipa.pdfIn PDF document text
    • http://braciszewska-klimek.pl/fck_files/file/47992102987.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16086d1f237bc7---59257374184.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d3f183e15c0---59895263859.pdfIn PDF document text
    • https://arerp.kr/data/file///79204258753.pdfIn PDF document text
    • https://fullprotec.com/ckfinder/userfiles/files/zezananenulel.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/2329552562.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160e40bc542bfc---bakagikinusiti.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/411526010d3066ff57a503abe8050f42/21762066157.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210803232215.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e130858f2c5---jetenesulupif.pdfIn PDF document text
    • http://snnet.kr/board_pds/fckeditor/2021/08/file/rixurabapad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=el+abc+del+liderazgo+john+maxwell+libro+pdf+gratisPDF 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_off0000d70e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD70E 11568 bytes
SHA-256: d46c63dd7ae35c2bda2e5019a8ccda0fab73b37ba36d7475b045fad69b224482
font_01_sfnt_off0000f1ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1EE 19232 bytes
SHA-256: ae3a90a7585a5feb291df08b767e33077dd8445e786cf7ef17ec6bc502194c29
font_02_sfnt_off00012331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12331 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1