Open-Xchange: Security Vulnerabilities
Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and username is altered in passdb, then OTP credentials can be cached so that same OTP reply is valid. An attacker able to observe an OTP exchange is able to log in as the user. If authentication happens over unsecure connection, switch to SCRAM protocol. Alternatively ensure the communcations are secured, and if possible switch to OAUTH2 or SCRAM. No publicly available exploits are known.
CVSS Score
6.8
EPSS Score
0.003
Published
2026-03-27
Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the credential will lead into full access to the affected component. Limit access to the doveadm http service port, install fixed version. No publicly available exploits are known.
CVSS Score
7.4
EPSS Score
0.003
Published
2026-03-27
Sending "NOOP (((...)))" command with 4000 parenthesis open+close results in ~1MB extra memory usage. Longer commands will result in client disconnection. This 1 MB can be left allocated for longer time periods by not sending the command ending LF. So attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Install fixed version, there is no other remediation. No publicly available exploits are known.
CVSS Score
4.3
EPSS Score
0.004
Published
2026-03-27
When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.
CVSS Score
5.3
EPSS Score
0.004
Published
2026-03-27
Dovecot has provided a script to use for attachment to text conversion. This script unsafely handles zip-style attachments. Attacker can use specially crafted OOXML documents to cause unintended files on the system to be indexed and subsequently ending up in FTS indexes. Do not use the provided script, instead, use something else like FTS tika. No publicly available exploits are known.
CVSS Score
4.3
EPSS Score
0.003
Published
2026-03-27
ManageSieve AUTHENTICATE command crashes when using literal as SASL initial response. This can be used to crash ManageSieve service repeatedly, making it unavailable for other users. Control access to ManageSieve port, or disable the service if it's not needed. Alternatively upgrade to a fixed version. No publicly available exploits are known.
CVSS Score
7.5
EPSS Score
0.004
Published
2026-03-27
A type check was missing when handling fonts in PDF.js, which would allow arbitrary JavaScript execution in the PDF.js context. This vulnerability affects Firefox < 126, Firefox ESR < 115.11, and Thunderbird < 115.11.
CVSS Score
8.8
EPSS Score
0.726
Published
2024-05-14
E-Mails exported as PDF were stored in a cache that did not consider specific session information for the related user account. Users of the same service node could access other users E-Mails in case they were exported as PDF for a brief moment until caches were cleared. Successful exploitation requires good timing and modification of multiple request parameters. Please deploy the provided updates and patch releases. The cache for PDF exports now takes user session information into consideration when performing authorization decisions. No publicly available exploits are known.
CVSS Score
5.3
EPSS Score
0.005
Published
2024-05-06
E-Mail containing malicious display-name information could trigger client-side script execution when using specific mobile devices. Attackers could perform malicious API requests or extract information from the users account. Please deploy the provided updates and patch releases. We now use safer methods of handling external content when embedding displayname information to the web interface. No publicly available exploits are known.
CVSS Score
6.5
EPSS Score
0.006
Published
2024-05-06
Content-ID based embedding of resources in E-Mails could be abused to trigger client-side script code when using the "show more" option. Attackers could perform malicious API requests or extract information from the users account. Exploiting the vulnerability requires user interaction. Please deploy the provided updates and patch releases. CID replacement has been hardened to omit invalid identifiers. No publicly available exploits are known.
CVSS Score
6.5
EPSS Score
0.005
Published
2024-05-06