Malicious PDF — malware analysis report

Static analysis result for SHA-256 de845294d89d6953…

MALICIOUS

PDF

68.9 KB Created: 2021-09-26 20:26:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: ebf0f04648d20a6e79cab12462caeba2 SHA-1: 0f3e51e2e512f407c23b6ba86e1a548de560bf11 SHA-256: de845294d89d69531d8be976553b4c93da8cf0e6da2d6e78236764fbd4e07fa8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, and it contains embedded JavaScript. The PDF also features a link farm pointing to numerous external PDF files hosted on various domains, some of which are identified as compromised CMS uploads. This suggests the document is designed to lure users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • 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://em-mould.com/ckfinder/userfiles/files/donegoxa.pdf In PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131774cce985---64179978397.pdfIn PDF document text
    • https://polenhosting.com/calisma2/files/uploads/37887585884.pdfIn PDF document text
    • http://www.badischer-kunstverein.de/ckfinder/userfiles/files/9094068094.pdfIn PDF document text
    • https://thegioidongphuc.net/ckfinder/userfiles/files/tagexotemorovejeledojifi.pdfIn PDF document text
    • https://gotoko.com/cmsv2/upload/files/40965193325.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/62216404959.pdfIn PDF document text
    • https://www.abrasco.org.br/ckfinder/userfiles/files/ruliv.pdfIn PDF document text
    • http://lienming-rubber.com/uploads/files/202109091516068477.pdfIn PDF document text
    • http://constantemails.com/userfiles/file/163047389760056038392.pdfIn PDF document text
    • http://madang.eu/f_pds/fck/file/butebolutuledetalowabu.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/lavinewugupewevimosulil.pdfIn PDF document text
    • https://kvzriu.org/images/file/98682299929.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/161314999cf967---63737648279.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/91341009234.pdfIn PDF document text
    • https://cometgroupinternational.com/ckeditor/ckfinder/userfiles/files/damuwilebereg.pdfIn PDF document text
    • http://vpsystem.com/files/fck/75644137808.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/duvazufap.pdfIn PDF document text
    • https://nghiepvu.udicmanpower.vn/uploads/news_file/boderitadomojofosijaziwal.pdfIn PDF document text
    • http://olguanaokulu.com/upload/file/70352266429.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/4mm1a6bdoqshrcu5bahcpd2g44/37596517562.pdfIn PDF document text
    • https://marjoyunlar.com/calisma2/files/uploads/9400849967.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6748283ff---52355444983.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=ps+touch+for+iphonePDF 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_off0000ae63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE63 10468 bytes
SHA-256: a429d0b103fb23044a45c933a8b3f8024a4c4fbf3f7b347d795ba86650dd9408
font_01_sfnt_off0000c627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC627 16240 bytes
SHA-256: df441df77ccd5dcfee4fae6c6268696fa44487aeb7a22cbc1a5d600446299c2e
font_02_sfnt_off0000ee5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1