Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b5751bbc1cfba6a…

MALICIOUS

PDF

86.7 KB Created: 2021-09-12 14:02:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 54b0fb58be7e6f5d5dfee93e08efd385 SHA-1: 6a38104abeda55fc4560b0139adbb0bf227e405a SHA-256: 5b5751bbc1cfba6a8792b7bd0e67aa09d455542e829517ddb6b67011c58f973e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external URIs and link farm heuristics, indicating its primary purpose is to redirect users to potentially malicious websites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://drafthe.ru/uplcv?utm_term=free+internet+radio+app+for+android PDF link annotation
    • http://ottuk-e.org/userData/board/file/51205615776.pdfIn PDF document text
    • http://handinks.com/ckfinder/images_store/files/gaxedovuta.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef74661f62---datawusilife.pdfIn PDF document text
    • http://cheapneasytrafficschool.com/CheapNEasyTrafficSchool/pa/trainstation/uploads/image/file/25492535366.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/mavegaxilijuxozajifojo.pdfIn PDF document text
    • http://adams-gold.ru/archive/image/file/64123117775.pdfIn PDF document text
    • https://chinese-wall.tw/upload/files/43450272061.pdfIn PDF document text
    • http://jiuxingchaoshi.com/uploads/file/010901513510.pdfIn PDF document text
    • https://aykutemlak.com/upload/ckfinder/files/nudiba.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613db7ec7fdce---13205484922.pdfIn PDF document text
    • https://kingbakerypans.com/userfiles/file/55055222555.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136c7b688e99---likurokokimotu.pdfIn PDF document text
    • http://savalis.ru/userfiles/file/luzapabozosagaw.pdfIn PDF document text
    • http://climtech.com/files/files/begebajenezamidita.pdfIn PDF document text
    • http://www.gulbaharsigorta.com/contentData/file/6081880344.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/denavapaludegugipuweladu.pdfIn PDF document text
    • http://lycee-elm.com/userfiles/file/zudogujazarixi.pdfIn PDF document text
    • http://canyonmeadows.org/userimages/bedapiwidovilejixunutipax.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/dowegaxubamugu.pdfIn PDF document text
    • http://apvn.info/userfiles/file/7418660476.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc214080b8---25431221691.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_off0000f0cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0CB 10252 bytes
SHA-256: 396bbd458e261a9eba7fbaacdcac67d24df26101b1101a252ff6e07a4e2d25f3
font_01_sfnt_off000107de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107DE 17624 bytes
SHA-256: e30bf5b4bc7f3774c5f1b84931d9d6853aa8f391b78e5af53266cba986e2f997
font_02_sfnt_off0001352f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1352F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1