Malicious PDF — malware analysis report

Static analysis result for SHA-256 843768fd8da9daf5…

MALICIOUS

PDF

134.0 KB Created: 2021-09-09 05:00:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 8086c1a90983f69b5b9b62e8274dcbd4 SHA-1: 12d24b27350d3ca8ea3c5042070851ebca3c78e0 SHA-256: 843768fd8da9daf5783d91b4e65f0ed7e0307b4131e04bc862fa4fb7cb73e2d1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. The presence of numerous external links, many hosted on potentially disposable domains, combined with urgency language in the document body, suggests a phishing lure. While no scripts were explicitly extracted, the PDF format itself can embed JavaScript for malicious actions, and the link farm heuristic points towards a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9768

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
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://castilloexterior.net/ckfinder/userfiles/files/26862241040.pdf In PDF document text
    • https://yesilkoyluleriz.biz/resimler/files/mebokukojigojinoxakisube.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/15891551342.pdfIn PDF document text
    • http://nage-z.com/ckfinder/userfiles/files/78408862299.pdfIn PDF document text
    • http://ipea.kr/userData/board/file/85836331596.pdfIn PDF document text
    • http://asia-test.informacittadino.net/media/files/jitukuwejujolaxegowoxode.pdfIn PDF document text
    • http://profstil.az/userfiles/file/25299565221.pdfIn PDF document text
    • http://stellarp.com/userfiles/file/pukumopuzowepovubami.pdfIn PDF document text
    • https://smwebtechnology.com/arishayurveda.com/userfiles/file/mezeresi.pdfIn PDF document text
    • https://ismet.com.br/ckfinder/userfiles/files/75298629300.pdfIn PDF document text
    • http://dotykbylinky.sk/_subory/subory/12629891365.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/dopunelumuto.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/55659355439.pdfIn PDF document text
    • http://townofwinslowin.com/flash/townofwinslowin.com/file/30858825121.pdfIn PDF document text
    • http://archgeo-leszno.pl/uploads/userfiles/files/43252088050.pdfIn PDF document text
    • http://rakkhunnursinghome.com/user_img/files/20503200586.pdfIn PDF document text
    • https://ryokanclub.com/FileData/ckfinder/files/20210909_EDCBE25884542424.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/73774384411.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/53191394462.pdfIn PDF document text
    • https://biroestarsa.hu/uploads/file/rutoregeguwojuz.pdfIn PDF document text
    • https://nusantarabet4d1.com/contents/files/14272431061.pdfIn PDF document text
    • http://hutnia.pl/userfiles/file/99612928039.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613344335c056---sujadojusepinarotumomuf.pdfIn PDF document text
    • https://cosmopolitanhotelbg.lastrada.bg/uploads/wysiwyg/files/62344612759.pdfIn PDF document text
    • https://tadimtursu.com/image/files/durulebuzuweruwipa.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/lexogomuzurozeraretora.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=off+road+4x4+gamesPDF 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_off0001a704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A704 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001bf16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BF16 19500 bytes
SHA-256: 07f0773a8e9e8815bc25ce56d21ed2a40a7d077f64bcb4af220a7c893971a12d
font_02_sfnt_off0001f236.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1F236 10564 bytes
SHA-256: 083acc0b20f52922dbe5881b1ed8e137063707f8da40147b1d2fc6b66c320019