Malicious PDF — malware analysis report

Static analysis result for SHA-256 cef1ef941dfb1c7f…

MALICIOUS

PDF

71.1 KB Created: 2021-09-19 04:25:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 54d2b6dccbdbf4a5b31ae49957a93c53 SHA-1: 63d55d8836afb334fdaa25edcfed48ff5d5df46e SHA-256: cef1ef941dfb1c7f47c3b652a7e03291e82ad7702b8c55798504af83b41a7ef4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the nature of the links, suggesting an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 5

  • 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.
  • 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://pixomot.ru/uplcv?utm_term=my+hero+academia+heroes+rising+movie PDF link annotation
    • https://congchungnguyenlieu.vnpec.xyz/uploads/files/72187326265.pdfIn PDF document text
    • http://corporatiegids.nl/uploads/files/nulexibumivarozidozapadet.pdfIn PDF document text
    • http://gloteckr.com/upload/editor/file/81898449511.pdfIn PDF document text
    • http://swaptoys.org/ckeditor/uploads/files/37777878597.pdfIn PDF document text
    • https://seeandhearbetter.ie/img/shop/contents/3304344644.pdfIn PDF document text
    • https://pre-www.bridge-academy.com/uploaded/ckeditor/files/gorurorixinavelipile.pdfIn PDF document text
    • http://mp-journal.com/media/file/pulapulafajelazadobut.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/mivirazopovarer.pdfIn PDF document text
    • http://yesfabric.com/images/upload/File/tedabap.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd8eea03af---50283844706.pdfIn PDF document text
    • http://mtecommerce.it/public/news/file/36918587063.pdfIn PDF document text
    • http://jan-fotografie.nl/upload/files/tisidanadewox.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/69415973266.pdfIn PDF document text
    • http://imobiliariaimperio.com/files/files/budobuma.pdfIn PDF document text
    • http://denda.co.kr/ckfinder/userfiles/files/35568513107.pdfIn PDF document text
    • https://parkettworld.com/upload/files/piwonadovoratewesimabasep.pdfIn PDF document text
    • http://eluvial.com/sites/all/sites/eluvial.com/files/xurinevifizexizibenevedoz.pdfIn PDF document text
    • https://kocarbon.vn/luutru/files/zoropusejojewo.pdfIn PDF document text
    • https://e-tta.com/app/webroot/userfiles/files/retusagid.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/15086681238.pdfIn PDF document text
    • http://arqing.es/ckfinder/userfiles/files/pekujuvemodoner.pdfIn PDF document text
    • http://plantessentialoil.com/upload/files/44451671330.pdfIn PDF document text
    • https://uslugiinzynierskie.eu/eurostyl/photos/file/dezudalane.pdfIn PDF document text
    • http://www.jfac.kr/ckfinder/userfiles/files/75938846643.pdfIn PDF document text
    • http://utuin.net/files/fckeditor/file/zorepixowapobevosemafuj.pdfIn PDF document text
    • http://xsjsbzrw.com/uploads/files/zesavazutusaxomur.pdfIn PDF document text
    • http://luatsugiadinhviet.com/upload/ck/files/88099353962.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_off0000b3b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3B1 16732 bytes
SHA-256: 56a261fddc489c84225e04f78fd5eca6437a7a3f7403577611acc721ce4fbbfc
font_01_sfnt_off0000ddb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5CA 10844 bytes
SHA-256: 317227b9daa5b95b092d6855286161336ae0e00b26a1148c7fb6f7acbb99fb77