Email disclosure via STARTTLS session fixation
Published May 29, 2023 · Updated Jan 14, 2025
Session fixation in Citadel through webcit-932 allows man-in-the-middle attackers to redirect a victim's email into their IMAP mailbox. Citadel's POP3 and IMAP STARTTLS state transition preserves an attacker-established authenticated session even though STARTTLS is valid only before authentication. Exploitation requires an active network position that can modify the client-server connection, and message disclosure depends on the victim client's behavior.
Summary
What happened
Session fixation in Citadel through webcit-932 allows man-in-the-middle attackers to redirect a victim's email into their IMAP mailbox. Citadel's POP3 and IMAP STARTTLS state transition preserves an attacker-established authenticated session even though STARTTLS is valid only before authentication. Exploitation requires an active network position that can modify the client-server connection, and message disclosure depends on the victim client's behavior.
The record
- CVE
- CVE-2021-37845
- Published
- May 29, 2023
- Updated
- Jan 14, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1557
- Attack vector
- network
- Privileges
- Unavailable
Timeline
How it unfolded
- May 29, 2023CVE publishedPublication date reported by the CVE source.
- Jan 14, 2025Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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