Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4350154108b7cab…

MALICIOUS

PDF

81.6 KB Created: 2021-09-09 12:59:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 43dc12d322a251a4cd91495733bfe065 SHA-1: 8915b0d5b849cf5640eacbb6eaac26f3a9bdec71 SHA-256: e4350154108b7cab6266ccc8946f9f3d9fc207a4597015414e9a2dd3edf75cc1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using such PDFs to host a large number of links, likely for SEO manipulation or to distribute malicious content. The presence of multiple external URIs and link farm characteristics strongly suggests an intent to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 https://medvor.ru/uplcv?utm_term=best+addon+kodi+2021 PDF link annotation
    • https://cfbadalona.net/ckdata/files/nasanuvaxivugoriwimomis.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/3k2v0jloha7q9ahl7lq58qg037/7563280957.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/rusisilivejutededena.pdfIn PDF document text
    • https://jpt.mysmartedu.com/uploadimages/files/puxatawinekadidowotud.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/gobesifodomiberev.pdfIn PDF document text
    • http://dlugopis.kbo.pl/ckfinder/userfiles/files/40285079310.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/q35c41c1i964p3rmuo0t9jdh36/8787990771.pdfIn PDF document text
    • http://longruiglass.com/ckfinder/userfiles/files/20210907_081442.pdfIn PDF document text
    • https://sonntag-immobilien.lu/userfiles/files/nogik.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///mafudarawame.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/88837227508.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/bi6rabct3qfecgd7ttk2atnj1r/rolixibebekudijijipemiju.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/42732034520.pdfIn PDF document text
    • http://vektorma.ru/uploads/assets/file/pibofitovum.pdfIn PDF document text
    • https://nutricount.cz/UserFiles/File/tudusajixawogaxagag.pdfIn PDF document text
    • http://nicolalazzarotto.com/userfiles/files/kozufesiz.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/16133dadd4dff2---pijumukazelidomixabo.pdfIn PDF document text
    • https://www.info-service.com.tw/plugin/ckeditor/ckfinder/userfiles/files/69943653216.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613495a4e8f11---47691911376.pdfIn PDF document text
    • https://portecitadelle.portecitadelle.ca/ckfinder/userfiles/files/gasagutalix.pdfIn PDF document text
    • https://istanajp.com/contents/files/visuxiluzalojutimemej.pdfIn PDF document text
    • http://weiken-rc.com/upload/files/12242167474.pdfIn PDF document text
    • https://sharks-cz.cz/images/file/3808419165.pdfIn PDF document text
    • https://gilbertems.com/videos/file/faratulokafagobadewoweju.pdfIn PDF document text
    • http://microsolder.hu/userfiles/files/2459260905.pdfIn PDF document text
    • http://chemsdano.com/upload/files/dorojafagiledag.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_off0000d71c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD71C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF33 10532 bytes
SHA-256: eb5158524e58df4428d0c0a5f146e88f397e0f9930c9bbc273866136d609e99f
font_02_sfnt_off00010773.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10773 19088 bytes
SHA-256: 7a5c8bf9c3bca0631225ea2fcb939014493fc7733421544a4763a6ff7ee4fceb