Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0e460fe3b477e51…

MALICIOUS

PDF

80.3 KB Created: 2021-09-14 13:11:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c84dda89bb793a5f5a922975333b3128 SHA-1: b25210704f5f754598ee52c77a7cf16798ef2688 SHA-256: a0e460fe3b477e51185939b345f4ddb5dce5312b19e356c26215c9f2b4596e32
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the nature of the heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://ntct-dz.com/ckfinder/userfiles/files/14505008017.pdf In PDF document text
    • http://maekuangudomthara.com/ckfinder/userfiles/files/kulakixosemajomefoli.pdfIn PDF document text
    • http://domplus.su/userfiles/files/sitejemosobovubikizod.pdfIn PDF document text
    • http://straub-online.ch/userfiles/files/16728694738.pdfIn PDF document text
    • https://washlounge.in/ckfinder/userfiles/files/malajosipirikavuxijaf.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/aca75067020c9e59734590c3f7c9bd1c/fikonerezesimikujawok.pdfIn PDF document text
    • https://egc.ecrom.work/syo/files/26302108325.pdfIn PDF document text
    • http://twilaw.com/files/files/nufuterutimasujalewonita.pdfIn PDF document text
    • http://uelzecht.lu/userfiles/files/48501947855.pdfIn PDF document text
    • http://ketnoikienthuc.com/upload/files/ridufesekipusufuz.pdfIn PDF document text
    • https://alistairmills.com/ckfinder/userfiles/files/vemupuxuxed.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/49626025180.pdfIn PDF document text
    • http://tctrack.vn/images/newtech/files/22072017745.pdfIn PDF document text
    • https://securitydm.eu/slicice/file/vijogudojegox.pdfIn PDF document text
    • http://lepal.sk/ckfinder/userfiles/files/16095557492.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b16750632b---55375535775.pdfIn PDF document text
    • http://www.gpe-el.pro/ckfinder/userfiles/files/11197854750.pdfIn PDF document text
    • http://yameitecl.com/ckfinder/userfiles/files/20210903_145117.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/ferimo.pdfIn PDF document text
    • https://marwaservicecenter.com/nbloom/fckuploads/file/vatomadalubumijafe.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613eedaebcd2a---devuzujinubile.pdfIn PDF document text
    • https://edusfera.pl/upload/file/nuvumodadujikasix.pdfIn PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec0a46d6da---venaterijatikoxakivanakeg.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/dajagegufifizedosetuze.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=com+sec+android+app+my+filesPDF 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_off0000d4de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4DE 10828 bytes
SHA-256: 3a4af444a9fc82d7362bfa387f705fa161a135af15b4c52639daaac954f9323e
font_01_sfnt_off0000edcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDCD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000105df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105DF 17656 bytes
SHA-256: fd6b25033181ab48fe2bbb5440232eda2560438e82e0af094ce26720cc162bba