Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc5ea935c2ceae3d…

MALICIOUS

PDF

82.3 KB Created: 2021-09-16 09:14:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1a663dce29c8ed73c759523d0a850bf8 SHA-1: 769f5f9bfa6e129f71c7e7c29df23a919dc8d263 SHA-256: bc5ea935c2ceae3d803a43a0d8d74d84794542babb171bc31ad205bb5d8907dc
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to domains that are either disposable or associated with compromised CMS uploads. The document body is heavily obfuscated and unreadable, suggesting it's designed to obscure its malicious intent rather than convey information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • 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.
  • 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://archism.ru/uplcv?utm_term=la+huesped+libro+pdf PDF link annotation
    • https://alansglobalservices.com/ckfinder/userfiles/files/rorawuwelar.pdfIn PDF document text
    • http://www.dgtrans.co.th/login/ckfinder/userfiles/files/84290227665.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/snf5k7rpcer6dcto4kkdku78b8/mutapu.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/39597621146.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/35808579334.pdfIn PDF document text
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/retes.pdfIn PDF document text
    • http://www.dgtrans.co.th/login/ckfinder/userfiles/files/kufer.pdfIn PDF document text
    • http://vinhthuan.asia/upload/files/golemetemoxosevixisaxuz.pdfIn PDF document text
    • http://baove24h.org/upload/files/7503416273.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/57751653898.pdfIn PDF document text
    • https://praktijkbinnenstad.nl/file/2869714368.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/15809826975.pdfIn PDF document text
    • http://kunbot.com/upload/files/zifom.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16131d61d1400b---95659159993.pdfIn PDF document text
    • http://buren-kompanie.de/userfiles/files/96477635877.pdfIn PDF document text
    • https://ipssecurityconsultants.com/ckfinder/userfiles/files/fopidemisetelud.pdfIn PDF document text
    • https://brawlcall.jordanadams.com/ckfinder/userfiles/files/nipipag.pdfIn PDF document text
    • https://a-metal.e-giant.net/archive/file/files/xalimuvubuxab.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/0d42185c1b9b95aa00dae5090559687a/54000909616.pdfIn PDF document text
    • http://kossuthdigisuli.hu/userfiles/file/50875845627.pdfIn PDF document text
    • http://www.sloepverhuur-debiesbosch.nl/upload/files/7322596863.pdfIn PDF document text
    • http://travellightnepal.com/userfiles/file/64190722209.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_off0000da48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA48 10592 bytes
SHA-256: 5081e4021fd93fe0764f274631447b96de3364098cf0418a8b96390c9578413d
font_01_sfnt_off0000f24c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF24C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A5E 18720 bytes
SHA-256: 1433b21fc0fb8302db055fae71fa8f54bfe8b692c2c8a2c09afb77a049a89a9b