Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecb00f51b92d8f64…

MALICIOUS

PDF

72.8 KB Created: 2021-09-28 17:17:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 40c2892cf3fdc7794013ded9bad6854a SHA-1: f12b0fc6d3943aabd19265f15ba13032ced9fe00 SHA-256: ecb00f51b92d8f64f4e1443ba0605271192fa38a75ab1779a07e4500a9676974
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on distinct domains. The presence of external URIs and the link farm characteristic suggest an attempt to distribute malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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 http://dmychadla.eu/UserFiles/File/jivobadexigavinulum.pdf In PDF document text
    • http://abwingssuffolk1.com/uploads/files/88799686437.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/wosidobigofa.pdfIn PDF document text
    • http://www.pilatesyoga.hr/files/files/93029137418.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/10029751678.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e23ca1e0a1---wukojasemevogogutesujo.pdfIn PDF document text
    • https://digitaldaya.com/imagenes/file/kimefawale.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612f8ce87254b---18857359092.pdfIn PDF document text
    • https://hamzakocakoglu.com/userfiles/file/palagaparajuzomuxebutun.pdfIn PDF document text
    • http://badaranquehablar.com/userfiles/files/kabujejeronaxa.pdfIn PDF document text
    • http://kemnhapkhau.com/upload/files/wigetar.pdfIn PDF document text
    • http://mehmetrasimmutlu.com/icerik/file/garabopojugifakefekiwepi.pdfIn PDF document text
    • https://fetogram.com/images/upload/files/93018524421.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/83583270180.pdfIn PDF document text
    • http://huspanda.com/data/ckfinder/files/19315899047.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/lavikiwusakazilerinodir.pdfIn PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/53593245214.pdfIn PDF document text
    • http://xn--djr00fsyfv0o5qgy9u.com/filespath/files/20210927115117.pdfIn PDF document text
    • http://baggiez.net/userfiles/file/nogexudawokixagopon.pdfIn PDF document text
    • https://people11people.gr/uploads/File/41047160618.pdfIn PDF document text
    • https://geelaboba.dswip.com/ci/userfiles/files/juxixegopogosadegajoda.pdfIn PDF document text
    • http://xmzs.org/userfiles/file/pezegokotigigetajibazos.pdfIn PDF document text
    • http://open.ua/uploads/ckeditor/files/14297925094.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=pokemon+go+walking+cheatPDF 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_off0000b6de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6DE 18152 bytes
SHA-256: 16a3e167140034afeb91f2c4003886dc1e2f79409cd062713deb33b5709b0faf
font_01_sfnt_off0000e56c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE56C 10588 bytes
SHA-256: 9d9c9af290701f97a0a0b8ec9b67ff9c2a207d934c57ee2804b90648a24720de
font_02_sfnt_off0000fd80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1