CVE-2021-3297
On Zyxel NBG2105 V1.00(AAGU.2)C0 devices, setting the login cookie to 1 provides administrator...
On Zyxel NBG2105 V1.00(AAGU.2)C0 devices, setting the login cookie to 1 provides administrator access.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
On Zyxel NBG2105 V1.00(AAGU.2)C0 devices, setting the login cookie to 1 provides administrator access.
- Record
CVE-2021-3297- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.2 High
AV:L/AC:L/Au:N/C:C/I:C/A:C - Weakness
- CWE-287
- Updated
- 2026-11-02
CVE List No score
On Zyxel NBG2105 V1.00(AAGU.2)C0 devices, setting the login cookie to 1 provides administrator access.
- Record
CVE-2021-3297- Updated
- 2026-11-02
EUVDEUVD-2021-26631 No score
On Zyxel NBG2105 V1.00(AAGU.2)C0 devices, setting the login cookie to 1 provides administrator access.
- Record
EUVD-2021-26631- Updated
- 2026-11-02
GitHub AdvisoriesGHSA-vqr2-c24p-rh7p
On Zyxel NBG2105 V1.00(AAGU.2)C0 devices, setting the login cookie to 1 provides administrator...
On Zyxel NBG2105 V1.00(AAGU.2)C0 devices, setting the login cookie to 1 provides administrator access.
- Record
GHSA-vqr2-c24p-rh7p- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-287
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Nuclei | Zyxel NBG2105 V1.00(AAGU.2)C0 - Authentication Bypass |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, Nuclei, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-3297 is a high vulnerability (CVSS 7.8) in Zyxel Nbg2105 Firmware, published January 26, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 20.5%, the 97th percentile. No source names a fixed version.
References
zyxel.com/us/en/support/security_advisories.shtml
github.com/nieldk/vulnerabilities/blob/main/zyxel%20nbg2105/Admin%20bypass
codeberg.org/nieldk/vulnerabilities/src/branch/main/zyxel%20nbg2105/Admin%20bypass
nvd.nist.gov/vuln/detail/CVE-2021-3297