CVE-2026-101042 (GCVE-0-2026-101042)

Vulnerability from cvelistv5 – Published: 2026-09-27 16:28 – Updated: 2026-09-30 15:28
VLAI
Title
Parse Server 9.0.0 Authentication Bypass via Unverified Provider Identity
Summary
Parse Server is an open-source backend server. In versions >= 9.0.0 < 9.10.1-alpha.10 and >= 8.0.2 < 8.6.91, the code-based authentication adapters (GitHub, Google Play Games, Instagram, LINE, LinkedIn, Microsoft, QQ, Spotify, WeChat, Weibo) verify the client's authorization code with the external provider on signup and on provider linking, but not when authentication data is supplied together with a username and password on the login endpoint. As a result, a low-privileged authenticated user can attach an arbitrary, unverified provider identity to their own account without the provider ever being contacted, spoofing an external identity toward application logic that trusts the linked provider ID. An attacker can also pre-hijack accounts: by claiming the provider ID of a victim who has not yet linked that provider, the victim's later legitimate sign-in with that provider resolves to the attacker's account. Only deployments configuring one of the affected code-based auth adapters are impacted. Versions 9.10.1-alpha.10 and 8.6.91 fix the issue by running the adapter's credential verification on the login and challenge endpoints and rejecting a provider identity already linked to another user. As a workaround, disable the affected code-based auth adapters.
Severity
7.4 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
6.4 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-30 15:27 UTC
CWE
  • CWE-287 - Improper Authentication
Assigner
References
Impacted products
Vendor Product Version
parse-community parse-server Affected: 9.0.0 , < 9.10.1-alpha.10 (semver)
Unaffected: 9.10.1-alpha.10 (semver)
Create a notification for this product.
parse-community parse-server Affected: 8.0.2 , < 8.6.91 (semver)
Unaffected: 8.6.91 (semver)
Create a notification for this product.
Date Public
2026-09-13 00:00
Credits
MR-pentestGuy mtrezza
Show details on NVD website
To clipboard 

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Tags
Taxonomy of the tags.





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.



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.