Malicious PDF — malware analysis report

Static analysis result for SHA-256 b26fe6a9672c6e23…

MALICIOUS

PDF

73.3 KB Created: 2021-09-14 15:49:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e45d38c037e6d5d7a8652e6f42ee3cb4 SHA-1: 5a59e314656a5cc84e088f68af98e8228e202691 SHA-256: b26fe6a9672c6e2329802a6a07476fb8463e3050bbac0a443d4926d01a92b28d
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier strongly indicated maliciousness, and the presence of external URIs suggests an attempt to redirect the user to potentially harmful content or for SEO manipulation. No scripts were extracted, but the overall structure and URL distribution point towards a malicious intent to leverage external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 4

  • 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://coretry.ru/uplcv?utm_term=rich+dad+poor+dad+sinhala+book PDF link annotation
    • http://buyyoutubecomments.com/ci/userfiles/files/baxogigorizawida.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/15006004900.pdfIn PDF document text
    • https://laatjehuisweerstralen.nl/upload/file/gupelisube.pdfIn PDF document text
    • https://infrastone.com/userfiles/files/40744175476.pdfIn PDF document text
    • https://guclupin.com/calisma2/files/uploads/16264477564.pdfIn PDF document text
    • https://www.la-melodie-des-saveurs.fr/ckfinder/userfiles/files/91548524070.pdfIn PDF document text
    • https://100tmt.com/uploadimage/files/20210902122021.pdfIn PDF document text
    • http://vonschickenfremont.com/uploads/files/ruvowabewim.pdfIn PDF document text
    • http://omegapizza.net/uploads/files/97995112256.pdfIn PDF document text
    • http://farmandari-sarvestan.ir/images/news/files/43820250782.pdfIn PDF document text
    • http://semanbio.com/upload/files/tumibejoxivawogope.pdfIn PDF document text
    • https://www.bbmnetlicitacoes.com.br/cms/ckfinder/upload/files/77036466666.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/91738597988.pdfIn PDF document text
    • http://nincity.de/inline/file/posipavorefujaro.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210906135320.pdfIn PDF document text
    • https://mma-montessori.com/admin/ckfinder/userfiles/files/dekodifizizubede.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/zutopamibatejuvotifufo.pdfIn PDF document text
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/86832375764.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/vonan.pdfIn PDF document text
    • http://ukicda.com/admin/fckeditor_upfiles/file/2021090521145980554.pdfIn PDF document text
    • http://alcantara.cz/data/file/balapolifexexigibavegivaf.pdfIn PDF document text
    • https://atrax.eu/userfiles/file/97793461837.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/tuzogagejerebobidufebelir.pdfIn PDF document text
    • https://linkevicius.com/upload/galery/file/66139698912.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_off0000bd2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD2C 10660 bytes
SHA-256: 84847a23d730334a960d6dda550eabf6624a0715502e26e152eaffd565b7350d
font_01_sfnt_off0000d537.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD537 16328 bytes
SHA-256: 6b0bbb21401d7793949952051b8fda6ece88b653f358bfe89f867747ceb8666e
font_02_sfnt_off0000ff40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1