Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb1aee5ceaac91cb…

MALICIOUS

PDF

76.9 KB Created: 2021-09-19 18:19:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e4bd68adc91a202e095629b513c18b7e SHA-1: a675ee567c70d1e0532a12267775d628f1004f2f SHA-256: fb1aee5ceaac91cb137c4be2774bf10a5fc63f6d749094f1a879db7b8fa4f73d
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as malicious, including a high-severity alert for random URL links and a medium-severity alert for being a link farm on disposable hosting. The embedded URLs and the overall structure suggest an attempt to redirect users to potentially harmful sites, likely for phishing or malware distribution. While no scripts were explicitly extracted, the nature of the PDF and its links points towards an attack pattern involving malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://queure.ru/uplcv?utm_term=how+to+block+sites+on+mobile PDF link annotation
    • https://wendi101.com/userfiles/file/tuwizafarunogapunokisaga.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/gaxuzexasudomakefadobe.pdfIn PDF document text
    • http://embeddedhr.com/ckfinder/userfiles/files/bodopojunudo.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/tutagasedaroparatud.pdfIn PDF document text
    • https://wintechindia.in/ckfinder/userfiles/files/87314920086.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/tafeninugebutope.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/93019113381.pdfIn PDF document text
    • http://jfhcoaching.nl/userfiles/files/36125042344.pdfIn PDF document text
    • https://rowsontw.com/shopadmin/upload/files/sitevururubojurafubenu.pdfIn PDF document text
    • http://depcip.com/app/views/panel/ckfinder/userfiles/files/30382149606.pdfIn PDF document text
    • http://wakesup.org/userfiles/file/1085330927.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/fagujikikunojuxazimikabu.pdfIn PDF document text
    • https://evergreencans.com/userfiles/file/21245308409.pdfIn PDF document text
    • https://crcnueva.naturasoftware.com/uploads/images/files/82226560913.pdfIn PDF document text
    • https://shreenathtechnologies.com/userfiles/file/13689636727.pdfIn PDF document text
    • http://veterinarioassociatopacinidallatorre.eu/userfiles/files/vumedaradivoxatipovifo.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/56554186683.pdfIn PDF document text
    • http://partnercable.com/files/jejoxusirinadeb.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/vinuzevubifimipuz.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/161403b1762b96---21678546934.pdfIn PDF document text
    • http://seattledesis.com/fckeditor/file/tetumapewafoweresiravogup.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/87418884210.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_off0000c99e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC99E 10436 bytes
SHA-256: 72734b25e29cc0607d64d585f6162bfd72e126152321c3f597d1315e19ec8dc2
font_01_sfnt_off0000e14c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE14C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f95e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF95E 17236 bytes
SHA-256: 9de00978032284e75245bf86a3757ce1a8a6067992a14856b9bf18922c6c2fb4