CVE-2019-10691
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the...
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
- Record
CVE-2019-10691- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Updated
- 2026-11-02
CVE List No score
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
- Record
CVE-2019-10691- Updated
- 2026-11-02
EUVDEUVD-2019-2485 No score
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
- Record
EUVD-2019-2485- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-7m29-wr8r-5c2m
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the...
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
- Record
GHSA-7m29-wr8r-5c2m- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVALPINE-CVE-2019-10691
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
- Record
ALPINE-CVE-2019-10691- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSV
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
- Record
CVE-2019-10691- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Show 6 moreShow less
OSVDEBIAN-CVE-2019-10691
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
- Record
DEBIAN-CVE-2019-10691- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2019-10691
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
- Record
UBUNTU-CVE-2019-10691- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVopenSUSE-SU-2019:1312-1 No score
Security update for dovecot23
This update for dovecot23 fixes the following issues:
Security issue fixed:
- CVE-2019-10691: Fixed a denial of service via reachable assertion when processing invalid UTF-8 characters (bsc#1132501).
This update was imported from the SUSE:SLE-15:Update update project.
- Record
openSUSE-SU-2019:1312-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2024:10726-1 No score
dovecot23-2.3.16-1.6 on GA media
These are all security issues fixed in the dovecot23-2.3.16-1.6 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:10726-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2025:14715-1 No score
dovecot24-2.4.0-1.1 on GA media
These are all security issues fixed in the dovecot24-2.4.0-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2025:14715-1- Updated
- 2026-11-02
OSVSUSE-SU-2019:0997-1 No score
Security update for dovecot23
This update for dovecot23 fixes the following issues:
Security issue fixed:
- CVE-2019-10691: Fixed a denial of service via reachable assertion when processing invalid UTF-8 characters (bsc#1132501).
- Record
SUSE-SU-2019:0997-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
dovecotAlpine:v3.10 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.11 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.12 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.13 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.14 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.15 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.16 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.17 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.18 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.19 |
before 2.3.6-r0 | 2.3.6-r0 |
Show 14 moreShow less
| Package | Affected | Fixed |
|---|---|---|
dovecotAlpine:v3.20 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.21 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.22 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.23 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.24 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.8 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotAlpine:v3.9 |
before 2.3.6-r0 | 2.3.6-r0 |
dovecotDebian:12 |
before 1:2.3.4.1-4 | 1:2.3.4.1-4 |
dovecotDebian:13 |
before 1:2.3.4.1-4 | 1:2.3.4.1-4 |
dovecotDebian:14 |
before 1:2.3.4.1-4 | 1:2.3.4.1-4 |
dovecot23SUSE:Linux Enterprise Module for Server Applications 15 |
before 2.3.3-4.13.1 | 2.3.3-4.13.1 |
dovecot23openSUSE:Leap 15.0 |
before 2.3.3-lp150.11.1 | 2.3.3-lp150.11.1 |
dovecot23openSUSE:Tumbleweed From an advisory covering 22 CVEs |
before 2.3.16-1.6 | 2.3.16-1.6 |
dovecot24openSUSE:Tumbleweed From an advisory covering 24 CVEs |
before 2.4.0-1.1 | 2.4.0-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| affected | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-10691 is a high vulnerability (CVSS 7.5) in Dovecot, published April 18, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.80%, the 86th percentile. Fixed in dovecot 2.3.6-r0.
References
openwall.com/lists/oss-security/2019/04/18/3
dovecot.org/list/dovecot-news/2019-April/000406.html
lists.opensuse.org/opensuse-security-announce/2019-05/msg00000.html
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QHFZ5OWRIZGIWZJ5PTNVWWZNLLNH4XYS
security.gentoo.org/glsa/201908-29
nvd.nist.gov/vuln/detail/CVE-2019-10691
Show 35 moreShow less
github.com/advisories/GHSA-7m29-wr8r-5c2m
security.alpinelinux.org/vuln/CVE-2019-10691
security-tracker.debian.org/tracker/CVE-2019-10691
suse.com/support/update/announcement/2019/suse-su-20190997-1
bugzilla.suse.com/1132501
ubuntu.com/security/CVE-2019-10691
cve.org/CVERecord?id=CVE-2019-10691