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CVE-2026-71259 (GCVE-0-2026-71259)

Vulnerability from cvelistv5 – Published: 2026-08-05 12:26 – Updated: 2026-08-10 11:46
VLAI
Title
ESPHome external_components file:// Scheme Validation Bypass Leading to Remote Code Execution
Summary
ESPHome through 2026.7.0-dev contains an operator-precedence bug in the cv.url validator in esphome/config_validation.py. Because binds tighter than , any file: URI passes validation regardless of netloc. This validator gates the field of the external_components YAML directive's git source schema, which is passed to (git supports file:// natively).
Severity
8.6 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-05 15:29 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
esphome esphome Affected: 0 , ≤ 2026.7.0 (semver)
guessed Create a notification for this product.
Date Public
2026-08-05 12:26
Credits
Alibek Baxtiyorov
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

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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.
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  • 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.


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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.