Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f6353ab7d38a86a…

MALICIOUS

PDF

81.0 KB Created: 2021-09-17 22:19:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: d2520d135fa3b20991494c3938e0909c SHA-1: 0dc0f4ac70caf0216ac0f7b47b458f6c2be28b3e SHA-256: 5f6353ab7d38a86a37435adb5ee07cd01d8c57fa3a44b2c1bc4a69c77ffa6eaf
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which are part of a link farm designed to redirect users to various download sites. The ML classifier strongly indicated maliciousness, and the heuristic firings confirm the presence of external URIs and a link farm structure. While no scripts were explicitly extracted, the PDF's structure and the high number of suspicious URLs suggest an attempt to deliver malware or lead users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://chcial.ru/uplcv?utm_term=ps4emus+apk+download PDF link annotation
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b6fd4ac811---34621865246.pdfIn PDF document text
    • http://xn--80aguejfegacgj0ad.xn--p1ai/pict/file/werasogimaduletiso.pdfIn PDF document text
    • https://sanipacific.com/attachment/file/riwofilajafesorip.pdfIn PDF document text
    • https://tiemhoamo.com/data/dulieu/files/69342500547.pdfIn PDF document text
    • http://autowagon.it/userfiles/files/wosaj.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/38488994585.pdfIn PDF document text
    • https://atlastoursntravels.com/userfiles/file/95985426947.pdfIn PDF document text
    • http://physio-praxismitte.de/userfiles/kawimilizilesaruwig.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/kewapudunago.pdfIn PDF document text
    • http://vom-ragnaroek.de/uploads/file/24282625647.pdfIn PDF document text
    • https://osiindia.org/ckfinder/userfiles/files/bunetomareka.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/ckfinder/userfiles/files/jinuzobumefa.pdfIn PDF document text
    • http://koutingchina.com/upload/files/28995022558.pdfIn PDF document text
    • http://agenziaimmobiliarecannavo.eu/userfiles/files/xisizolitobed.pdfIn PDF document text
    • https://www.pessin-location.fr/ckfinder/userfiles/files/tuvafavebavan.pdfIn PDF document text
    • http://otestmanager.org/club/data/userfiles/file/20210906145730.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/b057468c1c0eab1c9173556e257d4500/retikobilikegi.pdfIn PDF document text
    • http://tandprotheses.com/ckfinder/userfiles/files/72250184016.pdfIn PDF document text
    • https://havilahbuilders.com/userfiles/file/85203364606.pdfIn PDF document text
    • https://olamare.com/img/uploaded/file/kigubisigeder.pdfIn PDF document text
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/73963863447.pdfIn PDF document text
    • https://viboot.traigiongthuha.com/ckfinder/userfiles/files/20454939520.pdfIn PDF document text
    • https://groupunsur3.com/contents/files/563197942.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/1500328127.pdfIn PDF document text
    • http://jcpingie.be/public/files/kisazoruvumisaguwade.pdfIn PDF document text
    • https://vonia.mikludava.lt/images/files/dawekukezudarexik.pdfIn PDF document text
    • https://greenlakepaint.com/ckfinder/userfiles/files/suzelakatijeduxa.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_off0000d777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD777 10620 bytes
SHA-256: 96e9f0945939ae9d648be6c26009c06ae707afd786997dd4a4723efaea97c635
font_01_sfnt_off0000efd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD9 18192 bytes
SHA-256: f457d84a15f3b1fd0f3d1d01a34a71ea0efaab3a55fa090e969599243830b60c
font_02_sfnt_off00011e25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1