Malicious PDF — malware analysis report

Static analysis result for SHA-256 9161c45f993697b0…

MALICIOUS

PDF

68.5 KB Created: 2021-09-27 07:58:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 357c56ec796ab06e6c005d64b0003554 SHA-1: d6fc5400a8c444675223912da9f23be3331c4978 SHA-256: 9161c45f993697b09ca8a16367b92315cb5afe54b84a7af25ca2ffbaa07296a0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as malicious due to its structure, which resembles a phishing lure with an image overlay and a clickable action. It contains numerous links to potentially disposable domains, with one high-severity finding pointing to studiomedicoveterinariobellucci.eu. While no scripts were explicitly extracted, the PDF structure and the presence of external links suggest an attempt to redirect the user to a malicious site for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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.
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://sys-svinding.dk/userfiles/file/66116877180.pdf In PDF document text
    • http://baovekhucongnghiep.com/upload/files/70915165440.pdfIn PDF document text
    • http://etcad.net/np/upfile/file/judulowipifuxapuv.pdfIn PDF document text
    • https://webmenuplus.com/images/file/68190334335.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/97506557880.pdfIn PDF document text
    • http://xn--9i1b14lwsg1seumdzsx.com/upload/fckeditor/file/5858798008.pdfIn PDF document text
    • http://hotelpenza58.ru/ckfinder/userfiles/files/19681866455.pdfIn PDF document text
    • http://kdwatch.net/upload/files/2021092109471242.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/dawiferigobutajaxidi.pdfIn PDF document text
    • https://aljuboori.com/userfiles/files/21218015213.pdfIn PDF document text
    • http://balogmihaly.hu/UserFiles/file/rategalusuk.pdfIn PDF document text
    • http://rinsacars.com/files/others/17875176.pdfIn PDF document text
    • http://agierresrl.it/userfiles/files/lalapawitaniriput.pdfIn PDF document text
    • http://teleserviciomalaga.com/ckfinder/userfiles/files/pedosum.pdfIn PDF document text
    • http://hmondo.com/userData/board/file/73651392323.pdfIn PDF document text
    • http://wirtrauenuns.ch/images/file/97657271180.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/29950eb92cee07314eeefb1899b7b5ef/488020647.pdfIn PDF document text
    • http://monticellotownship.org/userfiles/file/dawukajoduwovukalupatad.pdfIn PDF document text
    • http://1night2day.com/UserFiles/file/73813207127.pdfIn PDF document text
    • https://quatden.vn/webroot/img/files/tesovonu.pdfIn PDF document text
    • http://bulmarconsult.com/files/nidixofevirufera.pdfIn PDF document text
    • http://xyr59.com/filespath/files/20210927123251.pdfIn PDF document text
    • https://propiedades.net/ckfinder/userfiles/files/6677259629.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=glencoe+algebra+1+chapter+12+resource+masters+pdfPDF 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_off0000ad7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD7B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c58d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC58D 14436 bytes
SHA-256: e76009d300683c0102eca2a053cc05537591d39788369a1f41706826a41c1a86
font_02_sfnt_off0000e9ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9CE 11428 bytes
SHA-256: 5fde99c417dc7aa44e451a5517be548464c93799efbe781d5477444ccf5f0415