CVE-2026-43798
A single crafted SSH message gives an unauthenticated network attacker an out-of-bounds stack write of attacker-controlled length and content against any application built on swift-nio-ssh. This vulnerability is addressed in swift-nio-ssh version 0.14.1.
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
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
A single crafted SSH message gives an unauthenticated network attacker an out-of-bounds stack write of attacker-controlled length and content against any application built on swift-nio-ssh. This vulnerability is addressed in swift-nio-ssh version 0.14.1.
- Record
CVE-2026-43798- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-121
- Updated
- 2026-11-02
EUVDEUVD-2026-63655
A single crafted SSH message gives an unauthenticated network attacker an out-of-bounds stack write of attacker-controlled length and content against any application built on swift-nio-ssh. This vulnerability is addressed in swift-nio-ssh version 0.14.1.
- Record
EUVD-2026-63655- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
NVD
A single crafted SSH message gives an unauthenticated network attacker an out-of-bounds stack write of attacker-controlled length and content against any application built on swift-nio-ssh. This vulnerability is addressed in swift-nio-ssh version 0.14.1.
- Record
CVE-2026-43798- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-121
- Updated
- 2026-11-02
OSV
A single crafted SSH message gives an unauthenticated network attacker an out-of-bounds stack write of attacker-controlled length and content against any application built on swift-nio-ssh. This vulnerability is addressed in swift-nio-ssh version 0.14.1.
- Record
CVE-2026-43798- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-43798 is a critical vulnerability (CVSS 9.8) in Apple Swift-nio-ssh, published August 20, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.47%, the 40th percentile. No source names a fixed version.