Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbdc13c9568f3fef…

MALICIOUS

PDF

82.8 KB Created: 2021-09-01 20:15:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1805e668ffa5c4d3cb1385451872dd37 SHA-1: 8440498186498865d423a819f82a4a0ecd36983c SHA-256: cbdc13c9568f3fef90238bc7a0e79d15ec01d08f579a8b8c66a8d16c1d71a2e5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code or redirecting users. The presence of multiple links pointing to compromised WordPress upload directories and disposable hosting suggests a link farm designed to obscure the ultimate destination or host malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://jeansresource.com/js/ckfinder/userfiles/files/56584388542.pdf In PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/59svv6maskmhrnjb1q1l7g8h41/93907759587.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae7cce0c7e6---63424387770.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c37d74db6f1---94605739802.pdfIn PDF document text
    • http://abc-tel.ru/data/File/pakokab.pdfIn PDF document text
    • http://charivne.info/images/file/85369421564.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/af4d197ff0f7de3df40f03e438485a7f/gaziraduvatipejiz.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/virojanofagupixosa.pdfIn PDF document text
    • https://myclubowners.com/userfiles/files/bivaropeguwinitoriluvazor.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/b584718caa8de06a11a983b8af7b6197/mojep.pdfIn PDF document text
    • https://its-bulgaria.bg/files/file/nivubegovakuz.pdfIn PDF document text
    • https://responsible-tourism-alliance.com/content_file/files/takulenozuvupi.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/telewurumagasefinokivir.pdfIn PDF document text
    • http://dakmet.pl/upload/76933545450.pdfIn PDF document text
    • https://edinburghpools.com/contents/files/dubilu.pdfIn PDF document text
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/8fd136784a8b229e6481e8f68ed984b6/35593888285.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/muguzuratidatulavinulafum.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/rd1vjj523vc4t6oo4d14fli2cd/fulozeke.pdfIn PDF document text
    • http://0965818789.com/CKEdit/upload/files/41655231145.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/t5cqj8itgfc2vo71qon8tviui0/56053811034.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa1bc845e8d---99710309020.pdfIn PDF document text
    • https://hijaulumut.com/contents//files/gewujabe.pdfIn PDF document text
    • http://goldartline.ua/userfiles/file/vapij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=traditional+pisco+sourPDF 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_off0000de53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE53 18376 bytes
SHA-256: f5aaa1b4d661f1e9fd176a51d0d2f182a6ce863a69be0a1979e579d9b3f8bdb6
font_01_sfnt_off00010dc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000125d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125D9 10436 bytes
SHA-256: ffbf5040abf9160b6b959baf190bb422eb30a80d7657e4374466c706d65b4d7d