Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f758455eea532eb…

MALICIOUS

PDF

70.8 KB Created: 2021-09-24 12:52:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 5c60e90259b50a9057431ad75fa8b452 SHA-1: 720f7edc54b4b15ab58df3107e4b1795ad890c7b SHA-256: 8f758455eea532eb5b95bc7aebd79c5ec50eef849c2007ab480162f321224458
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and is flagged by heuristics as a link farm on disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attack pattern involving directing users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://drafthe.ru/uplcv?utm_term=the+road+not+taken+by+robert+frost+questions+and+answers+pdf PDF link annotation
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614d0c9a915ea---56593069458.pdfIn PDF document text
    • http://rungruangsteel.com/public/upload/userfiles/files/nufixivasesuduliramow.pdfIn PDF document text
    • http://anduong-nhatthanh.com/uploads/news_file/lufakisibatufewi.pdfIn PDF document text
    • https://anup.bo/images/files/23251441693.pdfIn PDF document text
    • http://krajinar.cz/soubory/files/89359355281.pdfIn PDF document text
    • http://bodybybodyology.com/ckfinder/userfiles/files/turipikeruwekogux.pdfIn PDF document text
    • http://clarksville.net/wysiwygfiles/file/7363333192.pdfIn PDF document text
    • http://oio.cn/uploadfiles/files/8995464510.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/pikibitafovinafujiwibefi.pdfIn PDF document text
    • https://nguoixunghekiev.vn/userfiles/file/95696460717.pdfIn PDF document text
    • http://dynamicyunnan.com/ckfinder/userfiles/files/mobifalokoperibuv.pdfIn PDF document text
    • https://tourgardan.com/basefile/tourgardancom/files/pimosutano.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bdcba394db---ruvotugijovewimasijolo.pdfIn PDF document text
    • http://veiligheidssloten.nl/ckfinder/userfiles/files/lixoxim.pdfIn PDF document text
    • https://bloomeng.com/uploads/44954229337.pdfIn PDF document text
    • https://bushregenerators.com/userfiles/files/23901418221.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/24010099408.pdfIn PDF document text
    • https://mysmartedu.com/uploadimages/files/joraxajenidodatuvukit.pdfIn PDF document text
    • http://tangiahoang.vn/Images_upload/files/wawiromag.pdfIn PDF document text
    • http://lpsa.cz/userfiles/file/lejeb.pdfIn PDF document text
    • http://chiron-ventures.com/chiron/home/img/upload/files/210912090801627145o0wzw.pdfIn PDF document text
    • http://geometracosentino.com/userfiles/files/23334516028.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_off0000b18c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB18C 16224 bytes
SHA-256: e9b446fc0df057b4bbea93ce56bcb355325a54e6842be9a8cd48adb633fd8fc6
font_01_sfnt_off0000dae9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE9 11188 bytes
SHA-256: 0af0e6b0d479acb94973cfd26d058c88122f0d039574e1c2773ddf4a1063904a
font_02_sfnt_off0000f4b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1