Malicious PDF — malware analysis report

Static analysis result for SHA-256 2aefdb7be7e082ee…

MALICIOUS

PDF

93.6 KB Created: 2021-06-30 10:52:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7a665d3d2f5df0a4b7bc7bf8fb527831 SHA-1: 79e7fec4240b429e621d6fbad8b51ef6df9067c0 SHA-256: 2aefdb7be7e082ee2410ea14b53ccdf7bc008b428cd1ee49d0608577be47975a
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a high number of links pointing to various websites, many of which are hosted on compromised WordPress installations. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate these links are likely part of a link farm designed to obscure the true malicious destination. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, but the primary attack pattern involves directing users to potentially malicious external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

Heuristics 6

  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/be398c159ac06034fbc6ddbffdf2d85d/77138512604.pdf
    • http://kawoka.com/userfiles/file/62215187758.pdf
    • http://royalwedding.jp/images/blog//file/70367305462.pdf
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/icf971rau25ok5a880vf0nu320/nokedupifujidonanemopeju.pdf
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/b5fe84b83905b5b68ad44c08501f9815/76788305866.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0a37330d74---60883346804.pdf
    • http://tubietelbar.hu/uploadfile/86260411683.pdf
    • https://beruanglucu.com/contents//files/tuduzijezumapagudupusolo.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/fhinnjvv40frcpj3jkphm234mv/rekasegofurenoxo.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/fd298ca5262629800d487838616217f1/muderenimugukogireb.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098706e59b1a---moxujisoserugunu.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b631b2bb705---zobumapiwole.pdf
    • http://klinok-saintp.ru/files/46310730448.pdf
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/432ca6f6bf605e8c1dc1c3d3e41c4b4d/48594236505.pdf
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/g8spbh47gq352tp0l7ip0nttc6/kesoniguzut.pdf
    • http://canvangdientu.com/images/file/19804697424.pdf
    • http://toonesk.com/upload/21227451881.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094b98219ee9---ganivumalofew.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa62f9daa38---famamepadilonepufidijux.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075387c092c1---96713978944.pdf
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607edc73d5e29---zaliloduvuj.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9f1d34ff6---nidenifudoloduzuliba.pdf
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/1bpqmtrjb5d5i3vchf9eip30cs/70192933501.pdf
    • http://talleresjpg.es/img/file/5562361766.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=stop+getting+spam+emails
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f525.bin
8b91256c8f17518b7b558573433e6e63bb8528dc8bf25071965541129b7b6dcc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF525 17324 bytes
font_01_sfnt_off000122ac.bin
644c4cf2cdbc6b6c47c7bf521fac7744a686efe78999c5029991aeeb6944595e
pdf-font-stream PDF embedded font (sfnt) at offset 0x122AC 16220 bytes
font_02_sfnt_off00013869.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13869 16792 bytes
font_03_sfnt_off00015080.bin
0b79316a0f8db9f01baec5e0769e54b5cd55cdf909f456a69a1f9831b75d96f7
pdf-font-stream PDF embedded font (sfnt) at offset 0x15080 10572 bytes