Malicious PDF — malware analysis report

Static analysis result for SHA-256 648d2318ce5d1761…

MALICIOUS

PDF

94.4 KB Created: 2021-09-06 18:47:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ae7560dbe940b415878a27a0ce616537 SHA-1: 470192632c466660261005753f97261d8e207a36 SHA-256: 648d2318ce5d1761125e5edc2cc18981c461e941da4d6282436382247d6e5818
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. It functions as a link farm, containing numerous URLs pointing to potentially compromised websites and disposable hosting, suggesting an attempt to distribute phishing content or malware. The presence of many external URIs and link farm indicators strongly supports a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://chcial.ru/uplcv?utm_term=igcse+biology+classification+worksheets PDF link annotation
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d541de4425---dotumodavogej.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/6931751578.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/mivajepubovopekelikura.pdfIn PDF document text
    • http://pahsclassof2005.com/clients/d/d6/d61c4c031b0f3af13d3e88110ef3a3e1/File/buvekebuzobomutupisijug.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/c7be60a44f5c471b65927136c8e1b8c6/20620622385.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160bd25f7e8100---83754335998.pdfIn PDF document text
    • https://mudrun.com/home/mud/public_html/ckfinder/userfiles/files/13213362165.pdfIn PDF document text
    • https://confidence-ist.com/ckfinder/userfiles/files/47939134424.pdfIn PDF document text
    • http://tlw.ro/UserFiles/file/1752512019.pdfIn PDF document text
    • http://ajarnveerapong.com/UserFiles/file/vedopaluno.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160705ba1f11ca---18724971004.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076e2df5f72e---65720499432.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1610d34beea85f---22559633907.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160962cf8d8ad7---82998585774.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/f9f7d331f3003d4213d0a027440aadf4/dekake.pdfIn PDF document text
    • http://aaaexpressheating.com/userfiles/file/71448090637.pdfIn PDF document text
    • http://cuatudongsaigon.vn/uploads/files/28666666874.pdfIn PDF document text
    • http://czechnews.cz/userfiles/files/57283764382.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/50681116342.pdfIn PDF document text
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/4e86a48be4f1dc49df4c29398b123664/pulusivewixigikeladixuwow.pdfIn PDF document text
    • http://hongdacable.com/d/files/16857979518.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607e95c098334---piwibobenifora.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/cc8adfab669bbd2147b0bd0c674038dc/51799830877.pdfIn PDF document text
    • http://sooclose.eu/upload/File/nugowuxibozes.pdfIn 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://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_off000109dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DC 11000 bytes
SHA-256: c815696e24d9d663ad3871f0686668cdddb2196c974f9eb012234d2c7f628097
font_01_sfnt_off0001236f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1236F 18200 bytes
SHA-256: 570af7bc3f6a2dd2d906c436d701b54a0a86cfd27356e294c0e654b1dd2a012e
font_02_sfnt_off00015343.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15343 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1