Malicious PDF — malware analysis report

Static analysis result for SHA-256 25c81481e930d43f…

MALICIOUS

PDF

79.2 KB Created: 2021-09-14 13:01:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9bf2ccc4b6b1db1f85a0e579f729980b SHA-1: 6db9f2a34cf14c56c4966842f0e05aa69501210e SHA-256: 25c81481e930d43f73823f6ab95118ee41f6a62eb3b34a89c37e7c74b3ffbc4f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and is flagged 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 links are indicative of malicious activity, likely leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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 http://yjsyrj.com/userfiles/file/93650163837.pdf In PDF document text
    • http://sieuthibds.net/images/files/fidiluvekaxadadegovivo.pdfIn PDF document text
    • https://rajatotogroup1.com/contents/files/lakazi.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/161314b5d2f5d3---80563480192.pdfIn PDF document text
    • http://chikatere.com/Upload/files/wifadefokogiwofi.pdfIn PDF document text
    • https://assignmentmart.com/ckfinder/userfiles/files/23631977744.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/dulonitaxawijofozitivi.pdfIn PDF document text
    • http://rhoptik.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/58291035215.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/56027602074.pdfIn PDF document text
    • http://www.teeintact.com/admin/fckeditor/editor/filemanager/connectors/php/img/file/kozupizigidimilotoluxo.pdfIn PDF document text
    • https://ltes2.tw-goods.com/UserFiles/files/45493150087.pdfIn PDF document text
    • http://tubelessons.net/cms_images/file/lijifewife.pdfIn PDF document text
    • http://abwmountvernon.com/uploads/files/21354150296.pdfIn PDF document text
    • http://timavoshipsupply.it/userfiles/file/kumokomidizabalagumo.pdfIn PDF document text
    • http://captainkillmite.com/uploads/files/202109110306215195.pdfIn PDF document text
    • http://arabstina.com/ckfinder/userfiles/files/40058254721.pdfIn PDF document text
    • http://huspanda.com/data/ckfinder/files/3405680049.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/4e9ba9e1a063568b2c0dbb64feeebddf/dexelizedilunubez.pdfIn PDF document text
    • https://tiemhoahaibara.com/data/dulieu/files/51145476255.pdfIn PDF document text
    • http://spzpoz-zdunskawola.pl/upload/file/66394242317.pdfIn PDF document text
    • https://mkserwis.pl/userfiles/file/pivibubiwisonu.pdfIn PDF document text
    • http://www.smpnuenen.nl/images/files/48972323631.pdfIn PDF document text
    • https://valleyrentals.com/userfiles/file/barapal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=diamond+apk+mod+mlPDF 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_off0000d3e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E6 17672 bytes
SHA-256: e80bd798ba621355a1edf944bd49637dd622b10ba569f830f318cc664609fb1e
font_01_sfnt_off0001015d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1015D 10148 bytes
SHA-256: 40c88c5dd524cec71d8e2d7030c9bb1b673f3c5f589f08c846aa4f14a459a79c
font_02_sfnt_off000117df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1