Malicious PDF — malware analysis report

Static analysis result for SHA-256 35c122aafcfe50f2…

MALICIOUS

PDF

87.3 KB Created: 2021-06-30 00:34:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: b9525639c5765c5e4ef129cdf9d3c656 SHA-1: c2c64ca0ab0356e5bb2b28aba19ac75e8d1bdc90 SHA-256: 35c122aafcfe50f261ac6bf7048c05ef5c627c8da9bc7c2ccbedaab845361359
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://caudafotografia.com/userfiles/files/xujojetagajutedug.pdf In PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f87ac31fe---piwaporibevitevules.pdfIn PDF document text
    • https://plentis.eu/ckfinder/userfiles/files/jugegulijemitu.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a86fca120ee---perovu.pdfIn PDF document text
    • https://mk-promotions.com/ckfinder/userfiles/files/kokenavekagesutose.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608f3f04919a9---31266050150.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160ac7ec1d5d9f---63475651953.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/fegasokimixodopuvunuwe.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/t5cj745k2e237f6m6rvdogilst/zajiwefomatijikobeb.pdfIn PDF document text
    • https://cristalparkhotel.com/ckfinder/userfiles/files/juwufekusefonozusetotarov.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/c94fab9ad6ec5c9098eae63f1cfaa1eb/bebiga.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/45235489f094761620f22297fed4aafa/4360298637.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/2fb7e485dce5aca34ee42345b98513f1/sodetuzosap.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a32bc23db98---14221745224.pdfIn PDF document text
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/4e084c143b951d4ec50c4c11092f0cd2/50069999476.pdfIn PDF document text
    • http://aep-tc.com/cache/fck_files/file/mowenijedovazabinasul.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/55233099612.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=treatment+for+epilepsy+in+humansPDF 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://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_off0000f604.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF604 10800 bytes
SHA-256: fb6df6c1ebd7034ec3d417048a9d5a75bb0ebaa06aee03122f79f2354a6c3374
font_01_sfnt_off00010eb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EB7 17536 bytes
SHA-256: 4175877489a27b2b4756d15ff8c307c2c213b3a257fbe67444757c28e0b18cc6
font_02_sfnt_off00013cea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CEA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1