Resource exhaustion in Stalwartlabs Stalwart
CVE-2025-61600
Stalwart is a mail and collaboration server. Versions 0.13.3 and below contain an unbounded memory allocation vulnerability in the IMAP protocol parser which allows remote attackers to exhaust server memory, potentially triggering the system's out-of-memory (OOM) killer and causing a denial of service. The CommandParser implementation enforces size limits on its dynamic buffer in most parsing states, but several state handlers omit these validation checks. This issue is fixed in version 0.13.4. A workaround for this issue is to implement rate limiting and connection monitoring at the network level, however this does not provide complete protection.
Vulnerability class: DoS (Denial of Service)
EPSS: 0.005 (41.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Stalwartlabs Stalwart — versions < 0.13.4
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2025-61600?
- CVE-2025-61600 is a high-severity vulnerability in Stalwartlabs Stalwart, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2025-10-02.
- How severe is CVE-2025-61600?
- High severity. CVSS v3 base score is 7.5 out of 10.