CVE-2021-37845
An issue was discovered in Citadel through webcit-932. A meddler-in-the-middle attacker can...
An issue was discovered in Citadel through webcit-932. A meddler-in-the-middle attacker can fixate their own session during the cleartext phase before a STARTTLS command (a violation of "The STARTTLS command is only valid in non-authenticated state." in RFC2595). This potentially allows an attacker to cause a victim's e-mail messages to be stored into an attacker's IMAP mailbox, but depends on details of the victim's client behavior.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
3.7
An issue was discovered in Citadel through webcit-932. A meddler-in-the-middle attacker can fixate their own session during the cleartext phase before a STARTTLS command (a violation of "The STARTTLS command is only valid in non-authenticated state." in RFC2595). This potentially allows an attacker to cause a victim's e-mail messages to be stored into an attacker's IMAP mailbox, but depends on details of the victim's client behavior.
- Record
CVE-2021-37845- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
CVE List
3.7
An issue was discovered in Citadel through webcit-932. A meddler-in-the-middle attacker can fixate their own session during the cleartext phase before a STARTTLS command (a violation of "The STARTTLS command is only valid in non-authenticated state." in RFC2595). This potentially allows an attacker to cause a victim's e-mail messages to be stored into an attacker's IMAP mailbox, but depends on details of the victim's client behavior.
- Record
CVE-2021-37845- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
EUVDEUVD-2021-24324
3.7
An issue was discovered in Citadel through webcit-932. A meddler-in-the-middle attacker can fixate their own session during the cleartext phase before a STARTTLS command (a violation of "The STARTTLS command is only valid in non-authenticated state." in RFC2595). This potentially allows an attacker to cause a victim's e-mail messages to be stored into an attacker's IMAP mailbox, but depends on details of the victim's client behavior.
- Record
EUVD-2021-24324- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-hh3j-j42w-mrpm
3.7
An issue was discovered in Citadel through webcit-932. A meddler-in-the-middle attacker can...
An issue was discovered in Citadel through webcit-932. A meddler-in-the-middle attacker can fixate their own session during the cleartext phase before a STARTTLS command (a violation of "The STARTTLS command is only valid in non-authenticated state." in RFC2595). This potentially allows an attacker to cause a victim's e-mail messages to be stored into an attacker's IMAP mailbox, but depends on details of the victim's client behavior.
- Record
GHSA-hh3j-j42w-mrpm- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-37845
3.7
An issue was discovered in Citadel through webcit-932. A meddler-in-the-middle attacker can fixate their own session during the cleartext phase before a STARTTLS command (a violation of "The STARTTLS command is only valid in non-authenticated state." in RFC2595). This potentially allows an attacker to cause a victim's e-mail messages to be stored into an attacker's IMAP mailbox, but depends on details of the victim's client behavior.
- Record
UBUNTU-CVE-2021-37845- CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
Affected products
Affected packages
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-2021-37845 is a low vulnerability (CVSS 3.7) in Citadel Webcit, published May 29, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.66%, the 52nd percentile. No source names a fixed version.
References
uncensored.citadel.org/dotgoto?room=Citadel%20Security
uncensored.citadel.org/msg/2099264259
nostarttls.secvuln.info
nvd.nist.gov/vuln/detail/CVE-2021-37845
github.com/advisories/GHSA-hh3j-j42w-mrpm
ubuntu.com/security/CVE-2021-37845
uncensored.citadel.org/readfwd?go=Citadel
cve.org/CVERecord?id=CVE-2021-37845