CVE-2026-125063
Automation-controller: automation-controller: quadratic regex in schedule rrule validation allows an authenticated user to exhaust api web workers (denial of service)
A flaw was found in the rrule validation of schedules in automation controller. Several non-anchored regular expressions with lazy wildcard prefixes are applied to the user-supplied rrule value; when the expected DTSTART/RRULE tokens are absent, validation time grows quadratically with the length of the value. An authenticated user can submit a large token-free rrule through the REST API, including the schedule preview endpoint, which requires no resource-level permissions; validation runs synchronously in the API web worker, so a single such request occupies a worker for an extended time and repeated requests can exhaust the web worker pool, denying access to the API and web UI while the attack is sustained. The impact is limited to availability.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
Automation-controller: automation-controller: quadratic regex in schedule rrule validation allows an authenticated user to exhaust api web workers (denial of service)
A flaw was found in the rrule validation of schedules in automation controller. Several non-anchored regular expressions with lazy wildcard prefixes are applied to the user-supplied rrule value; when the expected DTSTART/RRULE tokens are absent, validation time grows quadratically with the length of the value. An authenticated user can submit a large token-free rrule through the REST API, including the schedule preview endpoint, which requires no resource-level permissions; validation runs synchronously in the API web worker, so a single such request occupies a worker for an extended time and repeated requests can exhaust the web worker pool, denying access to the API and web UI while the attack is sustained. The impact is limited to availability.
- Record
CVE-2026-125063- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-1333
- Updated
- 2026-11-09
EUVDEUVD-2026-120159
A flaw was found in the rrule validation of schedules in automation controller. Several non-anchored regular expressions with lazy wildcard prefixes are applied to the user-supplied rrule value; when the expected DTSTART/RRULE tokens are absent, validation time grows quadratically with the length of the value. An authenticated user can submit a large token-free rrule through the REST API, including the schedule preview endpoint, which requires no resource-level permissions; validation runs synchronously in the API web worker, so a single such request occupies a worker for an extended time and repeated requests can exhaust the web worker pool, denying access to the API and web UI while the attack is sustained. The impact is limited to availability.
- Record
EUVD-2026-120159- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-09
GitHub AdvisoriesGHSA-269p-w2wm-cfpf
A flaw was found in the rrule validation of schedules in automation controller. Several non...
A flaw was found in the rrule validation of schedules in automation controller. Several non-anchored regular expressions with lazy wildcard prefixes are applied to the user-supplied rrule value; when the expected DTSTART/RRULE tokens are absent, validation time grows quadratically with the length of the value. An authenticated user can submit a large token-free rrule through the REST API, including the schedule preview endpoint, which requires no resource-level permissions; validation runs synchronously in the API web worker, so a single such request occupies a worker for an extended time and repeated requests can exhaust the web worker pool, denying access to the API and web UI while the attack is sustained. The impact is limited to availability.
- Record
GHSA-269p-w2wm-cfpf- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-1333
- Updated
- 2026-11-09
NVD
A flaw was found in the rrule validation of schedules in automation controller. Several non-anchored regular expressions with lazy wildcard prefixes are applied to the user-supplied rrule value; when the expected DTSTART/RRULE tokens are absent, validation time grows quadratically with the length of the value. An authenticated user can submit a large token-free rrule through the REST API, including the schedule preview endpoint, which requires no resource-level permissions; validation runs synchronously in the API web worker, so a single such request occupies a worker for an extended time and repeated requests can exhaust the web worker pool, denying access to the API and web UI while the attack is sustained. The impact is limited to availability.
- Record
CVE-2026-125063- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-1333
- Updated
- 2026-11-09
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| published | EUVD, NVD | |
| products, published, references, severity, title | CVE List | |
| aliases, references | EUVD | |
| first indexed | GitHub Advisories |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-125063 is a medium vulnerability (CVSS 4.3) in Red Hat Ansible Automation Platform 2, published November 9, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.31%, the 24th percentile. No source names a fixed version.