CVE-2026-10650
warmcat libwebsockets SSH Protocol sshd.c lws_ssh_parse_plaintext resource consumption
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.
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
- Low
Exploit likelihood
What each source reports
CVE List Score used
6.9
warmcat libwebsockets SSH Protocol sshd.c lws_ssh_parse_plaintext resource consumption
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.
- Record
CVE-2026-10650- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C - CVSS 3.0
- 5.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C - CVSS 2.0
- 5.0
AV:N/AC:L/Au:N/C:N/I:N/A:P/E:POC/RL:OF/RC:C - Weakness
- CWE-400, CWE-404
- Updated
- 2026-11-02
EUVDEUVD-2026-34034
6.9
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.
- Record
EUVD-2026-34034- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-23jv-8gf4-7r88
5.5
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function...
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.
- Record
GHSA-23jv-8gf4-7r88- CVSS 4.0
- 5.5 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-400
- Updated
- 2026-11-02
NVD
5.5
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.
- Record
CVE-2026-10650- CVSS 4.0
- 5.5 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-400, CWE-404
- Updated
- 2026-11-02
OSVBELL-CVE-2026-10650
5.3
CVE-2026-10650 does not affect BellSoft software
- Record
BELL-CVE-2026-10650- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
OSV
5.5
warmcat libwebsockets SSH Protocol sshd.c lws_ssh_parse_plaintext resource consumption
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.
- Record
CVE-2026-10650- CVSS 4.0
- 5.5 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P - Weakness
- CWE-400, CWE-404
- Updated
- 2026-11-02
Show 5 moreShow less
OSVDEBIAN-CVE-2026-10650
5.5
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.
- Record
DEBIAN-CVE-2026-10650- CVSS 4.0
- 5.5 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Updated
- 2026-11-02
OSVOESA-2026-2668
5.3
libwebsockets security update
Libwebsockets (LWS) is a flexible, lightweight pure C library for implementing modern network protocols easily with a tiny footprint, using a nonblocking event loop.
Security Fix(es):
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.(CVE-2026-10650)
- Record
OESA-2026-2668- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-10650
5.5
A flaw has been found in warmcat libwebsockets up to 4.5.8. This issue affects the function lws_ssh_parse_plaintext of the file plugins/protocol_lws_ssh_base/sshd.c of the component SSH Protocol Handler. Executing a manipulation of the argument msg_len can lead to resource consumption. The attack may be launched remotely. The exploit has been published and may be used. This patch is called 3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498. A patch should be applied to remediate this issue.
- Record
UBUNTU-CVE-2026-10650- CVSS 4.0
- 5.5 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
OSVMGASA-2026-0442 No score
Updated libwebsockets packages fix a security vulnerability
warmcat libwebsockets SSH Protocol sshd.c lws_ssh_parse_plaintext resource consumption. (CVE-2026-10650)
- Record
MGASA-2026-0442- Updated
- 2026-11-02
OSVUSN-8822-1 No score
libwebsockets vulnerabilities
It was discovered that Libwebsockets incorrectly handled certain SSH protocol messages in its SSH protocol handler. A remote attacker could possibly use this issue to cause Libwebsockets to consume excessive resources, resulting in a denial of service. (CVE-2026-10650)
It was discovered that Libwebsockets incorrectly handled certain malformed CBOR data. A remote attacker could possibly use this issue to cause Libwebsockets to crash, resulting in a denial of service, or execute arbitrary code. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-78161)
- Record
USN-8822-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
libwebsocketsDebian:12 |
All versions, plus listed versions 4.1.6-34.1.6-3.14.3.2-14.3.2-24.3.2-3 Show 12 moreShow less4.3.2-44.3.3-14.3.3-1.14.3.3-1.1~exp14.3.5-14.3.5-24.3.5-34.3.5-44.3.5-4.14.3.5-54.3.5-64.3.5-7 |
None known |
libwebsocketsDebian:13 |
before 4.3.5-1+deb13u2, plus listed versions 4.3.5-14.3.5-1+deb13u1 |
4.3.5-1+deb13u2 |
libwebsocketsDebian:14 |
before 4.3.5-5, plus listed versions 4.3.5-14.3.5-24.3.5-34.3.5-44.3.5-4.1 |
4.3.5-5 |
libwebsocketsMageia:10 |
before 4.5.2-1.1.mga10 | 4.5.2-1.1.mga10 |
libwebsocketsMageia:9 |
before 4.3.2-1.1.mga9 | 4.3.2-1.1.mga9 |
libwebsocketsopenEuler:20.03-LTS-SP4 |
before 4.3.0-8.oe2003sp4 | 4.3.0-8.oe2003sp4 |
libwebsocketsopenEuler:22.03-LTS-SP4 |
before 4.3.0-8.oe2203sp4 | 4.3.0-8.oe2203sp4 |
libwebsocketsopenEuler:24.03-LTS-SP1 |
before 4.3.3-5.oe2403sp1 | 4.3.3-5.oe2403sp1 |
libwebsocketsopenEuler:24.03-LTS-SP3 |
before 4.3.3-5.oe2403sp3 | 4.3.3-5.oe2403sp3 |
libwebsocketsUbuntu:Pro:20.04:LTS |
before 3.2.1-3ubuntu0.1~esm2, plus listed versions 2.0.3-3build13.2.1-33.2.1-3ubuntu0.1~esm1 |
3.2.1-3ubuntu0.1~esm2 |
Show 4 moreShow less
| Package | Affected | Fixed |
|---|---|---|
libwebsocketsUbuntu:Pro:22.04:LTS |
before 4.0.20-2ubuntu1.1+esm1, plus listed versions 4.0.20-24.0.20-2ubuntu14.0.20-2ubuntu1.1 |
4.0.20-2ubuntu1.1+esm1 |
libwebsocketsUbuntu:Pro:24.04:LTS |
before 4.3.3-1.1ubuntu0.1~esm2, plus listed versions 4.3.2-44.3.3-14.3.3-1.1build14.3.3-1.1build24.3.3-1.1build34.3.3-1.1ubuntu0.1~esm1 |
4.3.3-1.1ubuntu0.1~esm2 |
libwebsocketsUbuntu:25.10 |
All versions, plus listed versions 4.3.5-1 |
None known |
libwebsocketsUbuntu:26.04:LTS |
before 4.3.5-3ubuntu1.1, plus listed versions 4.3.5-14.3.5-34.3.5-3ubuntu1 |
4.3.5-3ubuntu1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-10650 is a medium vulnerability (CVSS 6.9) in Warmcat Libwebsockets, published June 2, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.43%, the 37th percentile. Fixed in libwebsockets 4.3.5-1+deb13u2.
References
vuldb.com/vuln/367955
vuldb.com/vuln/367955/cti
vuldb.com/cve/CVE-2026-10650
vuldb.com/submit/830261
github.com/biniamf/pocs/tree/main/libwebsockets_sshd-parse-ic-unbounded-alloc
github.com/biniamf/pocs/blob/main/libwebsockets_sshd-parse-ic-unbounded-alloc/poc_sshd_unbounded_alloc.py
Show 15 moreShow less
github.com/warmcat/libwebsockets/commit/3f9f0c6ecaf0e6f3f219d30632c5d1f2479d7498
github.com/warmcat/libwebsockets
nvd.nist.gov/vuln/detail/CVE-2026-10650
github.com/advisories/GHSA-23jv-8gf4-7r88
docs.bell-sw.com/security/cves/CVE-2026-10650
github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10650.json
security-tracker.debian.org/tracker/CVE-2026-10650
advisories.mageia.org/MGASA-2026-0442.html
bugs.mageia.org/show_bug.cgi?id=36157
lists.fedoraproject.org/archives/list/[email protected]/message/KMAEZLLRGAX46TX4KZNYWZXYVIWBF3RU
openeuler.org/zh/security/security-bulletins/detail?id=openEuler-SA-2026-2668
ubuntu.com/security/CVE-2026-10650
cve.org/CVERecord?id=CVE-2026-10650
ubuntu.com/security/notices/USN-8822-1
ubuntu.com/security/CVE-2026-78161