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CVE-2026-45318 (GCVE-0-2026-45318)

Vulnerability from cvelistv5 – Published: 2026-05-15 21:28 – Updated: 2026-05-18 12:45
VLAI
Title
Open WebUI: Stored XSS via unsanitized Office/Excel/DOCX file preview rendering ({@html} without DOMPurify)
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, his advisory tracks a regression of the original Excel-preview XSS (CVE-2026-44549). The same root cause — XLSX.utils.sheet_to_html() output rendered via {@html excelHtml} without DOMPurify — was reintroduced sometime after v0.8.0 and is exploitable again This vulnerability is fixed in 0.9.3.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-18 12:44 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version CPE status
open-webui open-webui Affected: < 0.9.3
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.