Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c99aedcc92f2a12…

MALICIOUS

PDF

88.5 KB Created: 2021-07-25 03:50:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: e40408200f21e37e98b7367978c3b401 SHA-1: 3ec814b3512973951f899753d5cde45ac1675d4f SHA-256: 6c99aedcc92f2a12767116743fb3a6f678e6fcc7b4628d585a17f3a1ee7c9d40
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites hosting PDF files. This behavior is indicative of a link farm, often used for SEO manipulation or to distribute malicious content. ClamAV detection and ML classification further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://sentinels.ro/userfiles/file/rugapodij.pdf In PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac905b5cb80---wajefabubavod.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607439ee469ad---27906044165.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16084dc6d7f613---88959015396.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/160d1f05dbd124---87674373408.pdfIn PDF document text
    • http://rambud.pl/uploaded/file/2878365657.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/d1516eaec559d942965a0b8b4834c700/xedomawaz.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1608dec8cb4b03---konipikowevorajotokan.pdfIn PDF document text
    • http://moristas.com/userfiles/files/85967096707.pdfIn PDF document text
    • https://binarbaidfabrication.com/public_html/userfiles/file/85943361153.pdfIn PDF document text
    • http://fairway.cc/images/blog//file/1074388946.pdfIn PDF document text
    • https://local-atlas.ru/userfiles/files/mivorazafebuvigupopef.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/642d4780dbf538404b6361843fc27ba7/11568450206.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16096e1950d4b1---pufigigunanegubunukol.pdfIn PDF document text
    • http://nordicaluminium.ru/userfiles/file/tomivuvazo.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/32981d1356a664db3553a2686ff94fb8/xabem.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/94186384453.pdfIn PDF document text
    • https://porterbrothersltd.com/app/webroot/uploads/68787888347.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/02d0c00c58147ad1ce65042e712be34c/gudofaluvisebutinamu.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/3ef8cf710cce55f35c35356b9f3a45ca/75789386013.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/ac6859ac9bb4810492b59c4295af10d2/nowikipovezapoparazonopa.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/3a6fd580542b89c178de3da066f71831/foganunifuzobujuvo.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/towumipasiwuzupagagosizi.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160bbeb327f5db---ruripokukef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+write+bio+data+for+interviewPDF 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_off0000f4f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F0 17628 bytes
SHA-256: 6b95034957d14a07dcf69f14c0e7f6e8ccff7761745bbe9d305b4f7675afe9e8
font_01_sfnt_off00012365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12365 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013b7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B7C 10416 bytes
SHA-256: 7dd7791e6c9e8bec4bc731e6ee1e1765f64e7488ea61be7bde16e0eb0eb24237