CVE-2026-42604
MEDIUMActual has an OpenID `client_secret` Disclosure via Broken Authorization Guard in `/openid/config`
Title source: cnaDescription
Actual is a local-first personal finance tool. The `POST /openid/config` endpoint in Actual Budget's sync-server versions <= 26.4.0 exposes the full OpenID Connect configuration—including the OAuth2 `client_secret`—to any caller who knows the bootstrap password. The endpoint also lacks authentication and rate limiting, making the bootstrap password brute-forceable. Version 26.5.0 fixes the issue.
References (2)
Core 2
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/actualbudget/actual/security/advisories/GHSA-49v6-pqjq-xw55
X_Refsource_Misc x_refsource_misc
https://actualbudget.org/blog/release-26.5.0
Scores
CVSS v4
6.9
EPSS
0.0040
EPSS Percentile
31.5%
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-863
Status
published
Products (1)
actualbudget/actual
< 26.5.0
Published
Jun 12, 2026
Tracked Since
Jun 13, 2026