Malicious PDF — malware analysis report

Static analysis result for SHA-256 72c277aedd032d68…

MALICIOUS

PDF

82.3 KB Created: 2021-10-04 20:53:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b0ee9f56203bedb98f67091f011808d2 SHA-1: 93bcf8950d1547dfbfbfb4af90cdbf643ba78589 SHA-256: 72c277aedd032d6829f39810dc7f6c582dc2286f7189e10b660a04d954b84e28
106 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to other PDF files on various domains, flagged as a link farm on disposable hosting. The ML classifier strongly indicated maliciousness, and the presence of algorithmically generated URLs suggests an attempt to evade detection or distribute payloads. The primary attack pattern appears to be a lure or redirection mechanism, likely leading to further malicious content or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • 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://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16156be659b35e---jovuwusedutebogixije.pdf In PDF document text
    • http://kelvista.lt/images/files/66393977933.pdfIn PDF document text
    • http://ranahytta.com/ckfinder/userfiles/files/wirabijipokojifabazomix.pdfIn PDF document text
    • https://odontologosmalca.com/images/userfiles/file/15379008085.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/powefupozesazojemeg.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/28544837058.pdfIn PDF document text
    • http://dientrotiendathc.com/media/ftp/file/nenuzal.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/mesomidowijanusinujo.pdfIn PDF document text
    • https://ever.dacola.com/upload/files/lokazon.pdfIn PDF document text
    • https://childrencareandliteracysociety.org/userfiles/files/15151543907.pdfIn PDF document text
    • https://alwaysthesame.pt/site/upload/file/wuxozivanosazif.pdfIn PDF document text
    • http://sumosushingrill.com/uploads/files/lafejopaxisezew.pdfIn PDF document text
    • http://dorapeyzaj.com/userfiles/file/sipeboxotudoko.pdfIn PDF document text
    • http://caycanh.vn/images/fck/file/sasuparogarix.pdfIn PDF document text
    • http://rebeccafantarchitetto.it/userfiles/files/munogaku.pdfIn PDF document text
    • http://yeongwonenc.com/userfiles/file/63044450039.pdfIn PDF document text
    • http://boletin.alicantehosteleria.com/lib/ckfinder/userfiles/files/tonalax.pdfIn PDF document text
    • http://dichvuhangngay.vn/uploads/image/files/87488728290.pdfIn PDF document text
    • https://hantverkarenisandby.se/UserFiles/files/jelasadoxugu.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021092015424673499.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/xutuxutok.pdfIn PDF document text
    • https://glbtrader.com/userfiles/file/22612404578.pdfIn PDF document text
    • https://booburger.myagenda.cz/pictures/editor/files/pabitabifebomepabe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=react+table+filter+paginationPDF 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_off0000dada.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDADA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F1 10672 bytes
SHA-256: 2f6f7cbf9efd2ecc36d746e4854c648ccba32fe89b0a07b6fba744e48f5939ed
font_02_sfnt_off00010b3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B3E 18444 bytes
SHA-256: 02aa7814e2e757abae1b15c68896ad85e6f8b7dadd4fd2ac2891ef96e7d8750d