CVE-2021-26788
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input...
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input validation, which may cause a denial of service (DoS). To exploit the vulnerability, an attacker needs to have TCP connectivity to the target system. Receiving a maliciously crafted TCP packet from an unauthenticated endpoint is sufficient to trigger the bug.
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
7.5
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input validation, which may cause a denial of service (DoS). To exploit the vulnerability, an attacker needs to have TCP connectivity to the target system. Receiving a maliciously crafted TCP packet from an unauthenticated endpoint is sufficient to trigger the bug.
- Record
CVE-2021-26788- CVSS 3.1
- 7.5 High
CVSS:3.1/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 - Weakness
- CWE-20
- Updated
- 2026-11-02
CVE List No score
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input validation, which may cause a denial of service (DoS). To exploit the vulnerability, an attacker needs to have TCP connectivity to the target system. Receiving a maliciously crafted TCP packet from an unauthenticated endpoint is sufficient to trigger the bug.
- Record
CVE-2021-26788- Updated
- 2026-11-02
EUVDEUVD-2021-13575 No score
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input validation, which may cause a denial of service (DoS). To exploit the vulnerability, an attacker needs to have TCP connectivity to the target system. Receiving a maliciously crafted TCP packet from an unauthenticated endpoint is sufficient to trigger the bug.
- Record
EUVD-2021-13575- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-284q-vmqr-cv75 No score
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input...
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input validation, which may cause a denial of service (DoS). To exploit the vulnerability, an attacker needs to have TCP connectivity to the target system. Receiving a maliciously crafted TCP packet from an unauthenticated endpoint is sufficient to trigger the bug.
- Record
GHSA-284q-vmqr-cv75- Weakness
- CWE-20
- Updated
- 2026-11-02
OSV
7.5
Oryx Embedded CycloneTCP 1.7.6 to 2.0.0, fixed in 2.0.2, is affected by incorrect input validation, which may cause a denial of service (DoS). To exploit the vulnerability, an attacker needs to have TCP connectivity to the target system. Receiving a maliciously crafted TCP packet from an unauthenticated endpoint is sufficient to trigger the bug.
- Record
CVE-2021-26788- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| 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-2021-26788 is a high vulnerability (CVSS 7.5) in Oryx-embedded Cyclonetcp, published March 8, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.22%, the 68th percentile. No source names a fixed version.