Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad85392ce8186105…

MALICIOUS

PDF

80.8 KB Created: 2021-09-14 10:44:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 33306484e8ed09d386262b6a83628ba3 SHA-1: 1eee2d8dba58e54177be060d964fc10a5894a03b SHA-256: ad85392ce8186105e767ed2de4c8928a70495b50b26f356e856693e17073b53e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external domains, some of which are hosted on compromised CMS platforms. The embedded URLs suggest an attempt to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://smidgel.ru/uplcv?utm_term=how+to+print+to+pdf+in+mac PDF link annotation
    • https://contemporaryteas.in/admin/uploads/file/74297462112.pdfIn PDF document text
    • https://webmedcentralplus.com/userfiles/file/numupojudopuburuwufupazi.pdfIn PDF document text
    • http://lt101shop.com/userfiles/files/88788498722.pdfIn PDF document text
    • https://alident.centralcms.cloud/galeria/files/rovidonibetivux.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/rinuginogegexusarefan.pdfIn PDF document text
    • http://thegioimercedes.com/upload/files/12309000579.pdfIn PDF document text
    • https://dursunguney.com/userfiles/files/jolatojipomelesefofigebo.pdfIn PDF document text
    • https://oancora.com/ckfinder/files/29429252091.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/161351c6c908e0---69248773023.pdfIn PDF document text
    • https://dbmotorbrokers.com/userfiles/file/xixawasige.pdfIn PDF document text
    • http://home-plast.ru/foto/files/gagimokukaxafefadora.pdfIn PDF document text
    • http://chengzechem.com/upload/files/22507162228.pdfIn PDF document text
    • http://defhjdr.friend-match.com/upload/files/wanajiwuvuvuda.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd1fab2e66---navixege.pdfIn PDF document text
    • https://rotterdampools.com/contents/files/97667746994.pdfIn PDF document text
    • https://sakura-bashi.com/uploads/files/202108311721552936.pdfIn PDF document text
    • http://ytlcases.com/userfiles/file/lasem.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/usrq8g8bkkrsi02ig6392mdr6a/fikarojavu.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/23553146536.pdfIn PDF document text
    • https://lodoshosting.com/calisma2/files/uploads/niminemaxuno.pdfIn PDF document text
    • https://aykutemlak.com/upload/ckfinder/files/posozatijiwa.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/povirekilumujutena.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/33750234068.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/36352145469.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_off0000d635.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD635 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE4C 10512 bytes
SHA-256: cb313b50e0b58528accf975bd7c5a46c80b8e30d91c8791688160b46c76d27e7
font_02_sfnt_off00010632.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10632 18460 bytes
SHA-256: 75eb99b6b8b57d36841806e56f045ac170ca3415c2b392acffd82b14a85db6d3