CVE-2023-26433
When adding an external mail account, processing of IMAP "capabilities" responses are not limited...
When adding an external mail account, processing of IMAP "capabilities" responses are not limited to plausible sizes. Attacker with access to a rogue IMAP service could trigger requests that lead to excessive resource usage and eventually service unavailability. We now limit accepted IMAP server response to reasonable length/size. No publicly available exploits are known.
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
When adding an external mail account, processing of IMAP "capabilities" responses are not limited to plausible sizes. Attacker with access to a rogue IMAP service could trigger requests that lead to excessive resource usage and eventually service unavailability. We now limit accepted IMAP server response to reasonable length/size. No publicly available exploits are known.
- Record
CVE-2023-26433- 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-400
- Updated
- 2026-11-02
EUVDEUVD-2023-30253
When adding an external mail account, processing of IMAP "capabilities" responses are not limited to plausible sizes. Attacker with access to a rogue IMAP service could trigger requests that lead to excessive resource usage and eventually service unavailability. We now limit accepted IMAP server response to reasonable length/size. No publicly available exploits are known.
- Record
EUVD-2023-30253- 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
- 2026-11-03
GitHub AdvisoriesGHSA-f8cc-v72f-5rm2
When adding an external mail account, processing of IMAP "capabilities" responses are not limited...
When adding an external mail account, processing of IMAP "capabilities" responses are not limited to plausible sizes. Attacker with access to a rogue IMAP service could trigger requests that lead to excessive resource usage and eventually service unavailability. We now limit accepted IMAP server response to reasonable length/size. No publicly available exploits are known.
- Record
GHSA-f8cc-v72f-5rm2- 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-400
- Updated
- 2026-11-02
NVD
When adding an external mail account, processing of IMAP "capabilities" responses are not limited to plausible sizes. Attacker with access to a rogue IMAP service could trigger requests that lead to excessive resource usage and eventually service unavailability. We now limit accepted IMAP server response to reasonable length/size. No publicly available exploits are known.
- Record
CVE-2023-26433- 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-400
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-26433 is a medium vulnerability (CVSS 4.3) in Open-xchange Appsuite Backend, published June 20, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.15%, the 67th percentile. No source names a fixed version.
References
software.open-xchange.com/products/appsuite/doc/Release_Notes_for_Patch_Release_6219_7.10.6_2023-03-20.pdf
documentation.open-xchange.com/appsuite/security/advisories/csaf/2023/oxas-adv-2023-0002.json
seclists.org/fulldisclosure/2023/Jun/8
packetstormsecurity.com/files/173083/OX-App-Suite-SSRF-Resource-Consumption-Command-Injection.html
nvd.nist.gov/vuln/detail/CVE-2023-26433
github.com/advisories/GHSA-f8cc-v72f-5rm2