CVE-2026-45278 json
Nextcloud: Open Redirect in user_oidc login flow via protocol-relative URL bypass
published 5mo ago modified 3mo ago also EUVD-2026-33704
- cvss
- 3.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 14%
- public exploits
- 0
- none known
Summary
Nextcloud is an open source content collaboration platform. From version 6.1.0 to before version 8.2.2, an attacker can craft links that would redirect users to another website, when the victim uses the attackers link to log in via user OIDC. This issue has been patched in version 8.2.2.
Patch / fix
Is CVE-2026-45278 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5mo ago
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 3.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N |
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected products
- nextcloud security-advisories
Classification
- Weakness
-
- CWE-601 URL Redirection to Untrusted Site
References
-
github.com
/nextcloud/user_oidc/pull/1273
issue-tracking, patch
-
github.com
/nextcloud/security-advisories/security/advisories/GHSA-8wjr-5cg8-4w73
vendor-advisory
-
hackerone.com
/reports/3464925
permissions-required
Sources
- CVE List CVE-2026-45278
- NVD CVE-2026-45278
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.