Malicious PDF — malware analysis report

Static analysis result for SHA-256 991f3e66ca4723bb…

MALICIOUS

PDF

92.7 KB Created: 2021-09-08 23:31:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e1cca1a1d21779b0f9cade514c7514a4 SHA-1: bc26a7ae7a3184e1437b63b205679ee11336a103 SHA-256: 991f3e66ca4723bb66d14fb79c5285706e5babcfded77d61d280d90445e245d9
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134a470a1269---61268142919.pdf In PDF document text
    • http://locnuocvietmy.com/Images_upload/files/29423952039.pdfIn PDF document text
    • http://houstontca.org/Content/uploads/files/mumumugokuvite.pdfIn PDF document text
    • http://radecznica.pl/userfiles/file/sovamufewatipabolofil.pdfIn PDF document text
    • http://nct-vn.com/userfiles/file/81455225144.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134867495865---29271262156.pdfIn PDF document text
    • http://miyagi.chi-kara.net/Upload/files/mogilejeremunizilu.pdfIn PDF document text
    • http://etnorom.hu/pictures/dugadowevuzun.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-1/20210901151502929286.pdfIn PDF document text
    • http://dsraxys.com/uploads/91326025696.pdfIn PDF document text
    • http://kahounova.cz/userfiles/file/70715288152.pdfIn PDF document text
    • http://ytlcases.com/userfiles/file/piguraxas.pdfIn PDF document text
    • http://systemsbiology.at/uploads/assets/file/61531488288.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/vumubipeti.pdfIn PDF document text
    • https://phongkhamtamthan.net/uploadeditor/files/39871842584.pdfIn PDF document text
    • http://gemmacapitalgroup.com/foto/file/87390860636.pdfIn PDF document text
    • http://bxbrdh.marketsearching.com/upload/files/47210153896.pdfIn PDF document text
    • http://cityclick.it/userfiles/files/30776710892.pdfIn PDF document text
    • http://uniradioweb.info/userfiles/files/razirojaku.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///85286059727.pdfIn PDF document text
    • http://montpellier-businessplan.fr/mbp/upload/images/images/upload/ckfinder/19603822049.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/b95b7138e5a5028584b31eaf2aa31f54/bozonusu.pdfIn PDF document text
    • http://neteyes.eu/editor_up/21109052119.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=audio+player+android+studioPDF 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_off000105db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105DB 18028 bytes
SHA-256: 7c79434a2389ed488a1479195467441c0f2ff685bda721e02ae3316a913e9ccf
font_01_sfnt_off0001356b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1356B 10580 bytes
SHA-256: babd858b0d5c57e88460b7bf3465c64a8001318705eb1aad0b0ad669c0260d17
font_02_sfnt_off00014dba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DBA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1