Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6e6503a05c34388…

MALICIOUS

PDF

76.1 KB Created: 2021-06-15 18:32:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 2c580554d8e954d38b83ab5fd283d6c4 SHA-1: 18cea4b29b660b1360a170fd5276749f8d90f893 SHA-256: a6e6503a05c343882418490ea54da45d37ca5ab6bab1dd125e42a159af1b5857
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

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 and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://archism.ru/uplcv?utm_term=game+ppsspp+need+for+speed+most+wanted PDF link annotation
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/f4ae0799712dc0de966413c1e76d7169/gegeparexifufazisubo.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/kemevu.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc3ada65fc---86071639955.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/40817538060.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/f3c77422164ac1d067fd4851d7442619/jiweziditibofu.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/74308853802.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/1607270053f42d---12625320002.pdfIn PDF document text
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/7b671b32e5163eb7eeda9f3668ac86c0/tosogep.pdfIn PDF document text
    • http://dentish.ru/ckfinder/userfiles/files/19244039909.pdfIn PDF document text
    • http://bigcool.net/webroot/img/files/gadumokabiwugadorezoxebak.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/cf36666d6a169d229a94c2ea850b248f/mewiwenebiwezaz.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/xomevenofojiretasa.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca5462a84a---xulavujepukusesebotekem.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/4e02bfa70bdc388647f6bd57db3c4c7f/babewaweg.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_off0000eb18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB18 5280 bytes
SHA-256: bad537bb47650802eabb8150e95fb075beff559cff5ae36f451fce404027c77d
font_01_sfnt_off0000fd0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0B 10672 bytes
SHA-256: d8529571e10a5bc433af845a0d88f102237771060dffeb7e9fa8f43ce95326d3