Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a5fd3e8ab69513d…

MALICIOUS

PDF

69.6 KB Created: 2021-09-24 16:25:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5c736c1dcb67772ebd3ddd9fe2b94b1a SHA-1: f4aab15655fd75c6bdb558fd03734a31643b1265 SHA-256: 1a5fd3e8ab69513d86a6b9d3934c6ea04a19a68a9dcd26172858f60c1c1f131d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on disposable domains or compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly support its malicious nature. The embedded JavaScript likely facilitates the redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://coretry.ru/uplcv?utm_term=a20+update+android+11 PDF link annotation
    • http://kpotplace.com/uploads/files/nuzejudowabu.pdfIn PDF document text
    • http://taketty.xyz/js/ckfinder/userfiles/files/39817770850.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/56881487694.pdfIn PDF document text
    • http://lamekatus.ee/uploads/ckeditor/files/wukinozasejel.pdfIn PDF document text
    • http://hongphuc.vn/userfiles/file/jusolefiwajofazu.pdfIn PDF document text
    • http://phongthuydotho.vn/upload/files/zedopisozilomejisekope.pdfIn PDF document text
    • http://riverside-plaza.com/upload/userfile/files/28275672032.pdfIn PDF document text
    • https://izometal.net/mm/file/bevupeviwezezabegavifusej.pdfIn PDF document text
    • https://pinyardim.com/calisma2/files/uploads/bogoteginamojod.pdfIn PDF document text
    • http://makinsushi.com/uploads/files/78339409858.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/lajukewuzagerafuzewerof.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/9b43bd2cb4d6ea6dd767f8e390c93ac3/wadebarimonulomog.pdfIn PDF document text
    • https://raljob.com/userfiles/file/96073070325.pdfIn PDF document text
    • https://izr.fr/files/87742104686.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109080255018450.pdfIn PDF document text
    • http://theleadershipworks.com/PO2/UPFILE/userfiles/files/tikemixokave.pdfIn PDF document text
    • http://eggtesting.com/admin/uploads/file/9805299849.pdfIn PDF document text
    • http://doctour.hu/uploads/ckfinder/userfiles/files/61815041442.pdfIn PDF document text
    • http://bzws.zhanyougame.com/ckfinder/userfiles/files/zabegerota.pdfIn PDF document text
    • http://w-mill.jp/images/file/sepewovolir.pdfIn PDF document text
    • https://basealimentare.it/webroot/files/fck_uploads/File/tirimivitij.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ddca4c19fb.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/26107dcc08f4dd622a257c513e10338d/pakiserimetanujaniwa.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_off0000b160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB160 15516 bytes
SHA-256: 3c63effe27074090c7bb0721d908338b4c55dfa25260e5366e22c16f3909bb2a
font_01_sfnt_off0000d85a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD85A 10548 bytes
SHA-256: 1f0f521ac83e12abdde18261f9e54eb9d315bc4d5dd75915a567ffb13db01d7a
font_02_sfnt_off0000f096.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF096 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1