Malicious PDF — malware analysis report

Static analysis result for SHA-256 41c76842e3c5992d…

MALICIOUS

PDF

87.0 KB Created: 2021-10-08 13:51:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 9099d75e4e9ad93e4fa16e492a6d8bde SHA-1: 882ea6b1a574b4fb65593a2d02d52f7afc445300 SHA-256: 41c76842e3c5992dd24be5e7659defcd211efc2a4e5db32c87e3eded8769adae
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to various websites, many of which appear to be compromised CMS uploads or hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. No scripts were extracted, but the structure and URL analysis point to a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://slide-bearing.com/d/files/tinunewerulubo.pdf In PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614f7fa04d5e5---57694922448.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/a18f6f933f9e140a8b2faf7dd2520740/wunazorosejo.pdfIn PDF document text
    • http://mesterteto.hu/userfiles/file/37856947332.pdfIn PDF document text
    • https://quizai.com/uploads/files/45339086086.pdfIn PDF document text
    • http://retailjewellerindiaawards.com/userfiles/file/zikoxanamer.pdfIn PDF document text
    • https://uslugiinzynierskie.eu/eurostyl/photos/file/1581406423.pdfIn PDF document text
    • http://aokisuper.com/ckfinder/userfiles/files/bigikavizenuledetoja.pdfIn PDF document text
    • http://reopen911.info/media/file/pakebavinixonupuguledo.pdfIn PDF document text
    • http://oticonshop.net/ckfinder/userfiles/files/59851143978.pdfIn PDF document text
    • https://odontologosmalca.com/images/userfiles/file/tesinawej.pdfIn PDF document text
    • https://trisyscom.com/userfiles/file/bijaxawolasuw.pdfIn PDF document text
    • http://phuongsen.com/img-chamthi/files/xowoxigefoxuwumovi.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615e31e4438c3---49289196020.pdfIn PDF document text
    • http://msiutilities.biz/documents/22770450174.pdfIn PDF document text
    • http://kino-cosmik.ru/sadm_files/botasomakuzi.pdfIn PDF document text
    • http://bodegaadrover.com/userfiles/imagenes/82778911902.pdfIn PDF document text
    • http://nyitotthetvege.kastelyszallodak.hu/userfiles/files/libewedupasojum.pdfIn PDF document text
    • http://ormansagszive.hu/upload/file/45656176888.pdfIn PDF document text
    • http://donateagift.eu/userfiles/file/32715400679.pdfIn PDF document text
    • https://vzduchotechnickefiltry.cz/docs/difewaxaza.pdfIn PDF document text
    • http://www.farmaciapenil.es/userfiles/files/20118023213.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16137c646e3e31---60964714198.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=themes+in+fragments+by+ayi+kwei+armahPDF 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_off0000ed87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED87 18724 bytes
SHA-256: fdec6c8e69ae1234d2606bd2d6a71e56f0ae0d4ad36ea17d19d9ba34ee1fe286
font_01_sfnt_off00011d70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D70 10892 bytes
SHA-256: 4b3d58c1aca092efd188e21905735fc92ffad374693c87bb656aa95190dc9b06
font_02_sfnt_off0001368e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1368E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1