Session stays alive after failed 2FA in twofactor_gauthenticator
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- Low · Low · Low
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-613.
Summary
The alexandregz twofactor_gauthenticator plugin for Roundcube, versions from 0 before 4640889, does not destroy the server-side session after failed two-factor verification (CWE-613). An attacker who already has the user's password can ignore the logout redirect and keep the session alive, which lets them brute force the second-factor code.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Description from the CNA
The twofactor_gauthenticator plugin for Roundcube is vulnerable to session persistence after failed 2FA verification. Due to the lack of server-side session destruction, an attacker can ignore the logout redirect and keep the session alive. This may allow an attacker who obtains user's password to e.g. brute force the second-factor code. This issue was fixed in commit 4640889.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
No affected products listed by the sources yet.
Remediation
Apply commit 4640889 to the twofactor_gauthenticator plugin, which fixes this issue.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
alexandregz twofactor_gauthenticator 4640889
3 records Highest priority Priority LOW 3 LOW
Other records, highest priority first
- TI-2026-81071 Authentication bypass by spoofing in twofactor_gauthenticatorPriority LOW 28
- TI-2026-81069 Missing rate limiting in Roundcube twofactor_gauthenticator 2FA checksPriority LOW 28
Timeline
- 2026-10-27 Threatist record created from CVE-2026-107146
- 2026-10-27 Alias added: GHSA-v777-5g8j-qgq8
- 2026-10-27 Priority changed: MEDIUM → LOW
- 2026-11-04 CISA SSVC decision points changed
References
More alexandregz vulnerabilities
- TI-2026-81071 Authentication bypass by spoofing in twofactor_gauthenticator CVSS 4.0MEDIUM 6.3
- TI-2026-81069 Missing rate limiting in Roundcube twofactor_gauthenticator 2FA checks CVSS 4.0MEDIUM 6.3
Sources
- CVE-2026-107146 · CVE Program
- CVE-2026-107146 · NVD
- FIRST EPSS
- GHSA-v777-5g8j-qgq8 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences