Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8f11ce4f36abf55…

MALICIOUS

PDF

71.1 KB Created: 2021-06-07 18:55:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 8c4bdb722c44182de9771ca3b09a425c SHA-1: 9f9c5d4c1d532d7b1693b637845caa0a1e34aedc SHA-256: f8f11ce4f36abf55dcadca1b909dc863f163944cbc909713ce5beeef7bec7804
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The document functions as a link farm, containing numerous URLs that point to various websites, including those hosted on compromised CMS uploads and disposable domains. These links are likely intended to lead users to phishing pages or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://krisoc.ru/uplcv?utm_term=ketogenic+glucogenic+amino+acids+mnemonic PDF link annotation
    • https://widepolymers.com/userfiles/file/xudukaf.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a56a95d166---19117745651.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/5d45035f7d80056499126285f3578512/naxujiboxiwesujemifuva.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/66c7bf456a79ee62183c73e382f9ee93/loxogo.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098645432e5e---95129415199.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ddac0cd00e---wilawuvopubefokadi.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5de2a488c3---kazabapibadodakezixega.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/m17623ohmkvu5fpivv5e0lsrk2/nikoxawebumamaxix.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077a170cba9d---rufafowipaxelevu.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2655b0e2e0---14206891236.pdfIn PDF document text
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/40475641982.pdfIn PDF document text
    • http://esthebel.de/userfiles/file/zinagirozowasemu.pdfIn PDF document text
    • http://magnachip.cn/userfiles/file/20210523214808.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/594t5h8i42jtquutda6c1aaft7/27770557285.pdfIn PDF document text
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078a1fbb1af9---dazotatogixukexa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8CB 5132 bytes
SHA-256: d96f0c72300bb50c301f6e24b51bf99e6d5abd71b02abb689bd796fce237f17f
font_01_sfnt_off0000ea3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA3B 10388 bytes
SHA-256: 63740c4ebd731e70bd7d2ad1cca35950d2358438eef09cb66171eb17f9d1f6e0