Malicious PDF — malware analysis report

Static analysis result for SHA-256 3704bdee4066ae97…

MALICIOUS

PDF

75.1 KB Created: 2021-09-17 15:43:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: fddccfc21f3e75947d9d1759c3f7f48f SHA-1: 328093381c8d9f4ca4b88665632e6b9f45996b66 SHA-256: 3704bdee4066ae9708b0cb09399fd79556bf32de3b5058efebfc37e5fda5b7ed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, pointing to multiple compromised WordPress upload directories and disposable hosting sites. While no scripts were explicitly extracted, the presence of external URIs and the nature of the link farm suggest an attempt to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/161433125bf14a---30378119773.pdf In PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/e8d822fdbe5181d29188bed2a0f116a4/19808782918.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/32554901601.pdfIn PDF document text
    • https://kalyna.ua/sites/default/files/userfiles/file/1512497523.pdfIn PDF document text
    • https://emenu.hu/editor_up/57056386464.pdfIn PDF document text
    • http://e-hematologica.com/users/file/4046929073.pdfIn PDF document text
    • http://resheto.ru/users_images/fck/file/76903702954.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/161301fc69df00---jinomuxelajorokoxiwu.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/42492739961.pdfIn PDF document text
    • http://srihemkuntschoolint.com/slbdavbatala/userfiles/file/rudokiv.pdfIn PDF document text
    • https://hockeymro.ca/docs/file/96702567914.pdfIn PDF document text
    • https://clinicamanila.com/ckfinder/userfiles/files/kobetidajufeloj.pdfIn PDF document text
    • https://vanphongphamhienluong.com/upload/files/xobeloxux.pdfIn PDF document text
    • http://madinagirls.com/easydo%20v2.00/files/uploads/goletujerezepewa.pdfIn PDF document text
    • https://gloriamus.org/Uploads/userfiles/files/gapujizakuzazino.pdfIn PDF document text
    • https://artistaone.co/userfiles/files/mabetasosujuzirupotagibi.pdfIn PDF document text
    • http://hightopeducation.com/cms_uploaded/file/21571786141.pdfIn PDF document text
    • http://bannermaul.com/userData/board/file/kakulisamorizufavefe.pdfIn PDF document text
    • http://npas.ru/pic/file/22336281172.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/wikifexizolexi.pdfIn PDF document text
    • http://abogadosaguilar.com/ckfinder/userfiles/files/39275707412.pdfIn PDF document text
    • http://hantechwelding.com/userfiles/file/2021091105501573499.pdfIn PDF document text
    • http://imssp.by/data/images/fxeditor/file/nuxurowaratamekafojogeto.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=biology+book+pdf+class+10PDF 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_off0000c0d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0D1 17288 bytes
SHA-256: 683197321364ecdf1fb1e7053a1949c75f22fcfb5d7952184e5f61bf28fa10f2
font_01_sfnt_off0000ed81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED81 10936 bytes
SHA-256: cdc40377dc288cc42cbcef1f4f1c28c413150fba616d8488c18e1f71255cdb2d
font_02_sfnt_off0001069d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1069D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1