CVE-2026-86452
MISP Unauthenticated Mail Endpoints Allow Unbounded Storage Consumption and Request Flooding
Published Sep 7, 2026
CVSS 4.0 · 8.7 High
EPSS < 1%
KEV · Not listed
Description
Affected versions of MISP permit unauthenticated or weakly constrained request paths to perform persistent work without adequate input bounds or rate limiting.
The users/forgot password-reset endpoint accepted an attacker-controlled email value without first imposing a reasonable length bound or validating its format. That value was then used to create an audit log entry and queue a password-reset job, causing the supplied value to be persisted more than once per request. The commit explicitly states that an unbounded unauthenticated request field was stored twice per call with no throttle.
The fix adds:
- a maximum email input length of 1024 bytes;
- email-format validation before persistent work;
- a per-source pre-authentication request budget;
- HTTP 429 responses when that budget is exceeded;
- a 15-minute cooldown for API-access request emails;
- POST-only handling and CSRF protection for the API-access request endpoint.
The new flood filter is specifically intended to limit persistent storage costs from anonymous requests such as password resets, registrations, and failed REST authentication attempts.
Version affected: ≤2.5.45
The users/forgot password-reset endpoint accepted an attacker-controlled email value without first imposing a reasonable length bound or validating its format. That value was then used to create an audit log entry and queue a password-reset job, causing the supplied value to be persisted more than once per request. The commit explicitly states that an unbounded unauthenticated request field was stored twice per call with no throttle.
The fix adds:
- a maximum email input length of 1024 bytes;
- email-format validation before persistent work;
- a per-source pre-authentication request budget;
- HTTP 429 responses when that budget is exceeded;
- a 15-minute cooldown for API-access request emails;
- POST-only handling and CSRF protection for the API-access request endpoint.
The new flood filter is specifically intended to limit persistent storage costs from anonymous requests such as password resets, registrations, and failed REST authentication attempts.
Version affected: ≤2.5.45
Affected Products
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CVE record
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NVD configurations
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Red Hat packages
No data
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OpenCVE enrichment
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| MISP | MISP | unaffected |
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No data.
| Vendor | Product | Versions | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Misp | Misp |
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Remediation
Tracking
Advisories
Metrics
Attack Vector Network
Attack Complexity Low
Privileges Required None
Attack Requirements None
User Interaction None
Vulnerable System Confidentiality Impact None
Vulnerable System Integrity Impact None
Vulnerable System Availability Impact High
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
Attack Vector Network
Attack Complexity Low
Privileges Required None
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
User Interaction None
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.542% probability within 30 days)
Exploitation none
Automatable yes
Technical Impact partial
References
| Link | Providers |
|---|---|
| https://github.com/MISP/MISP/commit/d75d899be |
|
History
Sep 14, 2026 7:00 AM
Description updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Affected versions of MISP permit unauthenticated or weakly constrained request paths to perform persistent work without adequate input bounds or rate limiting. The users/forgot password-reset endpoint accepted an attacker-controlled email value without first imposing a reasonable length bound or validating its format. That value was then used to create an audit log entry and queue a password-reset job, causing the supplied value to be persisted more than once per request. The commit explicitly states that an unbounded unauthenticated request field was stored twice per call with no throttle. The fix adds: * a maximum email input length of 1024 bytes; * email-format validation before persistent work; * a per-source pre-authentication request budget; * HTTP 429 responses when that budget is exceeded; * a 15-minute cooldown for API-access request emails; * POST-only handling and CSRF protection for the API-access request endpoint. The new flood filter is specifically intended to limit persistent storage costs from anonymous requests such as password resets, registrations, and failed REST authentication attempts. Version affected: ≤2.5.45 | Affected versions of MISP permit unauthenticated or weakly constrained request paths to perform persistent work without adequate input bounds or rate limiting. The users/forgot password-reset endpoint accepted an attacker-controlled email value without first imposing a reasonable length bound or validating its format. That value was then used to create an audit log entry and queue a password-reset job, causing the supplied value to be persisted more than once per request. The commit explicitly states that an unbounded unauthenticated request field was stored twice per call with no throttle. The fix adds: - a maximum email input length of 1024 bytes; - email-format validation before persistent work; - a per-source pre-authentication request budget; - HTTP 429 responses when that budget is exceeded; - a 15-minute cooldown for API-access request emails; - POST-only handling and CSRF protection for the API-access request endpoint. The new flood filter is specifically intended to limit persistent storage costs from anonymous requests such as password resets, registrations, and failed REST authentication attempts. Version affected: ≤2.5.45 |
Sep 9, 2026 3:30 PM
First appearance in the feed. Affected versions updated. Affected vendors updated. Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Misp-project
Misp-project misp |
|
| CPEs | cpe:2.3:a:misp-project:misp:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Misp-project
Misp-project misp |
|
| Metrics |
cvssV3_1
|
Sep 8, 2026 3:30 PM
Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Sep 7, 2026 3:45 PM
First appearance in the feed. Affected vendors updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Misp
Misp misp |
|
| Vendors & Products |
Misp
Misp misp |
Sep 7, 2026 1:30 PM
Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Affected versions of MISP permit unauthenticated or weakly constrained request paths to perform persistent work without adequate input bounds or rate limiting. The users/forgot password-reset endpoint accepted an attacker-controlled email value without first imposing a reasonable length bound or validating its format. That value was then used to create an audit log entry and queue a password-reset job, causing the supplied value to be persisted more than once per request. The commit explicitly states that an unbounded unauthenticated request field was stored twice per call with no throttle. The fix adds: * a maximum email input length of 1024 bytes; * email-format validation before persistent work; * a per-source pre-authentication request budget; * HTTP 429 responses when that budget is exceeded; * a 15-minute cooldown for API-access request emails; * POST-only handling and CSRF protection for the API-access request endpoint. The new flood filter is specifically intended to limit persistent storage costs from anonymous requests such as password resets, registrations, and failed REST authentication attempts. Version affected: ≤2.5.45 | |
| Title | MISP Unauthenticated Mail Endpoints Allow Unbounded Storage Consumption and Request Flooding | |
| Weaknesses | CWE-400 CWE-770 |
|
| References |
| |
| Metrics |
cvssV4_0
|
