Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a811ad2306140da…

MALICIOUS

PDF

86.8 KB Created: 2021-09-19 13:14:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8a3771e4e25928390625f007832941e9 SHA-1: fd2a9df19aa2646eddf41540c8794d636894f3c1 SHA-256: 1a811ad2306140da221820efa17854eecb3fcd59b66d2272f25cfc50910602d3
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous external links, many of which point to other PDF files hosted on potentially disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF_RANDOM_URL_LINK heuristic specifically highlights a link to a PDF hosted on 'lucidareemantenerepavimentifaidate.it', suggesting a potential phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://dream-mebel.com/pic/file/64079701545.pdf In PDF document text
    • http://thehedgerowchronicles.com/ckfinder/userfiles/files/vivamulofizeko.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d240dc7a95---kejipesenutu.pdfIn PDF document text
    • http://garantc.ru/userfiles/file/lezusudojofobapuroj.pdfIn PDF document text
    • http://kes.org/upload/editor/files/57378171338.pdfIn PDF document text
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/93295149362.pdfIn PDF document text
    • http://vakaruinzinerija.lt/userfiles/file/62032217514.pdfIn PDF document text
    • https://learnrkb.jugalbandiresearch.com/ckfinder/userfiles/files/28856074746.pdfIn PDF document text
    • http://smsalumni1971.com/apadmin/uploads/userfiles/files/purefovimadagetofotuv.pdfIn PDF document text
    • http://rts-3.ru/upload/files/nomixixotita.pdfIn PDF document text
    • http://peterpan1996.it/userfiles/files/fenerorirubamiwilusew.pdfIn PDF document text
    • https://giraffeng.net/infodaily/gen-ckfinder/userfiles/files/mufesuxosuvumutowa.pdfIn PDF document text
    • http://location-appartement-venise.com/italie_documents/files/welogexofobus.pdfIn PDF document text
    • http://dvif.fr/userfiles/file/wovunovulolobobe.pdfIn PDF document text
    • http://aa-nusd.jp/xoramulubutamoragive.pdfIn PDF document text
    • http://filippodelvita.com/demo/userfiles/file/torukirepebarotuba.pdfIn PDF document text
    • http://moscowballet.ru/userfiles/file/97386882305.pdfIn PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/39337447696.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/64730216845.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/pipakad.pdfIn PDF document text
    • http://lasantitosrestaurant.com/userfiles/file/51828076785.pdfIn PDF document text
    • http://zzps.pl/userfiles/file/sajemulinojine.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/0d22bf51571c74d47bc5752154fa50ff/bulewugemi.pdfIn PDF document text
    • https://opsclown.it/ckfinder/userfiles/files/10862556254.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=fast+and+furious+9+free+download+moviePDF 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_off0000edb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000105c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105C7 17836 bytes
SHA-256: aea8f1deea1b214b8a6c76db2496ec3e19a57bdfcfbdc4ac206d833dadd3bd9c
font_02_sfnt_off000133dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133DC 10912 bytes
SHA-256: 6a774eafa2ae5e1133f952cd8817eff7314ba76b1a937495a91b562402fd2350