CVE-2026-67990 json
basecamp/upright at commit efe4f2e5254ac6e57e45d2261804cca74dbbca3f disables Rails CSRF protection for its Alertmanager and Prometheus prox…
published 2026-08-13 2 mo ago modified 2026-09-08 2 mo ago also EUVD-2026-58031
- cvss
- 5.4
- 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 7%
- public exploits
- 0
- none known
Summary
basecamp/upright at commit efe4f2e5254ac6e57e45d2261804cca74dbbca3f disables Rails CSRF protection for its Alertmanager and Prometheus proxy controllers. An unauthenticated attacker can induce a logged-in user's browser to submit requests that are forwarded to enabled upstream write or management endpoints, such as creating an Alertmanager silence or requesting a Prometheus reload. The final impact depends on the APIs enabled by the upstream services.
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N |
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N |
Classification
- Weakness
-
- CWE-352 Cross-Site Request Forgery
References
- github.com /basecamp/upright
- github.com /basecamp/upright/blob/efe4f2e5254ac6e57e45d2261804cca74dbbca3f/app/controllers/upright/alertmanager_proxy_con
- github.com /basecamp/upright/blob/efe4f2e5254ac6e57e45d2261804cca74dbbca3f/app/controllers/upright/prometheus_proxy_contr
- gist.github.com /Zykis1024/cec690012eecac53f408e78d2b569f06
Sources
- CVE List CVE-2026-67990
- NVD CVE-2026-67990
Fencer Vulns 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.