CVE-2025-61600
Unbounded Memory Allocation in Stalwart IMAP parser
Description
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.
INFO
Published Date :
Oct. 2, 2025, 10:15 p.m.
Last Modified :
Oct. 12, 2026, 3:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update Stalwart to version 0.13.4 or later.
- Implement network-level rate limiting and connection monitoring.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-61600.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-61600 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-61600
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-61600 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-61600 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Translated by [email protected]
Oct. 12, 2026
Action Type Old Value New Value Changed Translation Title: stalwart de stalwartlabs, Description: Stalwart es un servidor de correo y colaboración. Las versiones 0.13.3 e inferiores contienen una vulnerabilidad de asignación de memoria ilimitada en el analizador del protocolo IMAP que permite a atacantes remotos agotar la memoria del servidor, potencialmente activando el 'out-of-memory (OOM) killer' del sistema y causando una denegación de servicio. La implementación de CommandParser aplica límites de tamaño a su búfer dinámico en la mayoría de los estados de análisis, pero varios manejadores de estado omiten estas comprobaciones de validación. Este problema está solucionado en la versión 0.13.4. Una solución alternativa para este problema es implementar limitación de velocidad y monitoreo de conexiones a nivel de red, sin embargo, esto no proporciona protección completa. Title: stalwart de stalwartlabs, Description: Stalwart es un servidor de correo y colaboración. Las versiones 0.13.3 e inferiores contienen una vulnerabilidad de asignación de memoria ilimitada en el analizador del protocolo IMAP que permite a atacantes remotos agotar la memoria del servidor, potencialmente activando el 'out-of-memory (OOM) killer' del sistema y causando una denegación de servicio. La implementación de CommandParser aplica límites de tamaño a su búfer dinámico en la mayoría de los estados de análisis, pero varios manejadores de estado omiten estas comprobaciones de validación. Este problema está solucionado en la versión 0.13.4. Una solución alternativa para este problema es implementar limitación de velocidad y monitoreo de conexiones a nivel de red, sin embargo, esto no proporciona protección completa. -
CVE Translated by [email protected]
Oct. 08, 2026
Action Type Old Value New Value Added Translation Title: stalwart de stalwartlabs, Description: Stalwart es un servidor de correo y colaboración. Las versiones 0.13.3 e inferiores contienen una vulnerabilidad de asignación de memoria ilimitada en el analizador del protocolo IMAP que permite a atacantes remotos agotar la memoria del servidor, potencialmente activando el 'out-of-memory (OOM) killer' del sistema y causando una denegación de servicio. La implementación de CommandParser aplica límites de tamaño a su búfer dinámico en la mayoría de los estados de análisis, pero varios manejadores de estado omiten estas comprobaciones de validación. Este problema está solucionado en la versión 0.13.4. Una solución alternativa para este problema es implementar limitación de velocidad y monitoreo de conexiones a nivel de red, sin embargo, esto no proporciona protección completa. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'stalwartlabs', 'product': 'stalwart', 'versions': [{'status': 'affected', 'version': '< 0.13.4'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2025-61600', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2025-10-03T13:39:30.035358Z'} -
New CVE Received by [email protected]
Oct. 02, 2025
Action Type Old Value New Value Added Description 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-400 Added CWE CWE-789 Added Reference https://github.com/stalwartlabs/stalwart/commit/a8e631e881bded8128358732f18e02ca94a4e677 Added Reference https://github.com/stalwartlabs/stalwart/releases/tag/v0.13.4 Added Reference https://github.com/stalwartlabs/stalwart/security/advisories/GHSA-8jqj-qj5p-v5rr