Cyrus
Monthly
A double-free in the CalDAV calendar worker of Cyrus IMAP before 3.12.4 lets an authenticated calendar user crash that worker by sending a WebDAV PATCH request carrying PATCH-ACTION="BYPARAM@..." against a calendar resource that holds two or more properties of the matched kind. The vulnerability is reachable only with valid credentials and with the CalDAV/calendar component enabled (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H, CWE-415), and the assessed outcome is a worker crash/restart rather than data disclosure or code execution. No public exploit code has been identified and EPSS is low at 0.22% (12th percentile); CISA SSVC rates exploitation as 'none' and the issue as not automatable, so this is a bounded availability bug rather than a critical-priority one.
Cyrus IMAP before 3.12.4 exposes a Sieve-based mailbox existence oracle that allows authenticated users to enumerate private mailboxes belonging to other users and read shared mailbox annotation values. By crafting conditional Sieve filter scripts using `fileinto` branches and observing delivery outcomes during LMTP processing, an attacker can infer the existence of otherwise inaccessible mailboxes or annotation content through a side-channel. No public exploit exists and the vulnerability is not listed in CISA KEV; the EPSS risk is commensurately low, reflecting a medium-severity information disclosure limited to authenticated insiders.
Cyrus IMAP before 3.12.4 permits an authenticated sharee who holds the `maySetKeywords` ACL right on a shared mailbox to overwrite that mailbox's RFC 6154 `specialuse` annotation via a JMAP `Mailbox/set` request, a capability that should be restricted to the mailbox owner. By reassigning the shared mailbox to a system role such as Archive or Snoozed, the sharee can cause the victim's mail client to route messages into the now-shared folder, disclosing content beyond what was originally granted. No public exploit has been identified at time of analysis; vendor-released patches are available across three supported stable branches.
Cyrus IMAP before 3.12.4 exposes private calendar events and contacts to partially-privileged authenticated users through a broken ACL enforcement path in the CalDAV/CardDAV multiget REPORT handler. An attacker who already holds some shared DAV access to a target user's calendar or address book can include hrefs of unshared resources in a calendar-multiget or addressbook-multiget REPORT request, causing the server to return those resources without enforcing per-href access controls. The vulnerability is fixed across the 3.8, 3.10, and 3.12 release branches; no public exploit or CISA KEV listing has been identified.
Heap memory disclosure in Cyrus IMAP before 3.12.4 allows authenticated users to leak adjacent heap contents via a crafted JMAP blob ID. By issuing a JMAP blob download request using the internal format H<emailid>-<index> with an index value that exceeds the length of the blob_headers array, an attacker triggers an out-of-bounds read (CWE-125) and receives whatever heap memory follows the array in the server's response. The CVSS 3.1 score of 3.1 (Low) reflects the authentication requirement, high attack complexity, and limited confidentiality impact; no public exploit has been identified at time of analysis.
Cyrus IMAP before 3.4.2 allows remote attackers to cause a denial of service (multiple-minute daemon hang) via input that is mishandled during hash-table interaction. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Cyrus IMAP before 3.2.7, and 3.3.x and 3.4.x before 3.4.1, allows remote authenticated users to bypass intended access restrictions on server annotations and consequently cause replication to stall. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity. This Incorrect Permission Assignment vulnerability could allow attackers to access resources due to misconfigured permissions.
An issue was discovered in Cyrus IMAP before 2.5.15, 3.0.x before 3.0.13, and 3.1.x through 3.1.8. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. This Improper Privilege Management vulnerability could allow attackers to escalate privileges to gain unauthorized elevated access.
Cyrus IMAP 2.5.x before 2.5.14 and 3.x before 3.0.12 allows privilege escalation because an HTTP request may be interpreted in the authentication context of an unrelated previous request that arrived. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
The CalDAV feature in httpd in Cyrus IMAP 2.5.x through 2.5.12 and 3.0.x through 3.0.9 allows remote attackers to execute arbitrary code via a crafted HTTP PUT operation for an event with a long. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In the mboxlist_do_find function in imap/mboxlist.c in Cyrus IMAP before 3.0.4, an off-by-one error in prefix calculation for the LIST command caused use of uninitialized memory, which might allow. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Integer overflow in the index_urlfetch function in imap/index.c in Cyrus IMAP 2.3.19, 2.4.18, and 2.5.6 allows remote attackers to have unspecified impact via vectors related to urlfetch range checks. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Integer overflow in the index_urlfetch function in imap/index.c in Cyrus IMAP 2.3.19, 2.4.18, and 2.5.6 allows remote attackers to have unspecified impact via vectors related to urlfetch range checks. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The index_urlfetch function in index.c in Cyrus IMAP 2.3.x before 2.3.19, 2.4.x before 2.4.18, 2.5.x before 2.5.4 allows remote attackers to obtain sensitive information or possibly have unspecified. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A double-free in the CalDAV calendar worker of Cyrus IMAP before 3.12.4 lets an authenticated calendar user crash that worker by sending a WebDAV PATCH request carrying PATCH-ACTION="BYPARAM@..." against a calendar resource that holds two or more properties of the matched kind. The vulnerability is reachable only with valid credentials and with the CalDAV/calendar component enabled (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H, CWE-415), and the assessed outcome is a worker crash/restart rather than data disclosure or code execution. No public exploit code has been identified and EPSS is low at 0.22% (12th percentile); CISA SSVC rates exploitation as 'none' and the issue as not automatable, so this is a bounded availability bug rather than a critical-priority one.
Cyrus IMAP before 3.12.4 exposes a Sieve-based mailbox existence oracle that allows authenticated users to enumerate private mailboxes belonging to other users and read shared mailbox annotation values. By crafting conditional Sieve filter scripts using `fileinto` branches and observing delivery outcomes during LMTP processing, an attacker can infer the existence of otherwise inaccessible mailboxes or annotation content through a side-channel. No public exploit exists and the vulnerability is not listed in CISA KEV; the EPSS risk is commensurately low, reflecting a medium-severity information disclosure limited to authenticated insiders.
Cyrus IMAP before 3.12.4 permits an authenticated sharee who holds the `maySetKeywords` ACL right on a shared mailbox to overwrite that mailbox's RFC 6154 `specialuse` annotation via a JMAP `Mailbox/set` request, a capability that should be restricted to the mailbox owner. By reassigning the shared mailbox to a system role such as Archive or Snoozed, the sharee can cause the victim's mail client to route messages into the now-shared folder, disclosing content beyond what was originally granted. No public exploit has been identified at time of analysis; vendor-released patches are available across three supported stable branches.
Cyrus IMAP before 3.12.4 exposes private calendar events and contacts to partially-privileged authenticated users through a broken ACL enforcement path in the CalDAV/CardDAV multiget REPORT handler. An attacker who already holds some shared DAV access to a target user's calendar or address book can include hrefs of unshared resources in a calendar-multiget or addressbook-multiget REPORT request, causing the server to return those resources without enforcing per-href access controls. The vulnerability is fixed across the 3.8, 3.10, and 3.12 release branches; no public exploit or CISA KEV listing has been identified.
Heap memory disclosure in Cyrus IMAP before 3.12.4 allows authenticated users to leak adjacent heap contents via a crafted JMAP blob ID. By issuing a JMAP blob download request using the internal format H<emailid>-<index> with an index value that exceeds the length of the blob_headers array, an attacker triggers an out-of-bounds read (CWE-125) and receives whatever heap memory follows the array in the server's response. The CVSS 3.1 score of 3.1 (Low) reflects the authentication requirement, high attack complexity, and limited confidentiality impact; no public exploit has been identified at time of analysis.
Cyrus IMAP before 3.4.2 allows remote attackers to cause a denial of service (multiple-minute daemon hang) via input that is mishandled during hash-table interaction. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Cyrus IMAP before 3.2.7, and 3.3.x and 3.4.x before 3.4.1, allows remote authenticated users to bypass intended access restrictions on server annotations and consequently cause replication to stall. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity. This Incorrect Permission Assignment vulnerability could allow attackers to access resources due to misconfigured permissions.
An issue was discovered in Cyrus IMAP before 2.5.15, 3.0.x before 3.0.13, and 3.1.x through 3.1.8. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. This Improper Privilege Management vulnerability could allow attackers to escalate privileges to gain unauthorized elevated access.
Cyrus IMAP 2.5.x before 2.5.14 and 3.x before 3.0.12 allows privilege escalation because an HTTP request may be interpreted in the authentication context of an unrelated previous request that arrived. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
The CalDAV feature in httpd in Cyrus IMAP 2.5.x through 2.5.12 and 3.0.x through 3.0.9 allows remote attackers to execute arbitrary code via a crafted HTTP PUT operation for an event with a long. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In the mboxlist_do_find function in imap/mboxlist.c in Cyrus IMAP before 3.0.4, an off-by-one error in prefix calculation for the LIST command caused use of uninitialized memory, which might allow. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Integer overflow in the index_urlfetch function in imap/index.c in Cyrus IMAP 2.3.19, 2.4.18, and 2.5.6 allows remote attackers to have unspecified impact via vectors related to urlfetch range checks. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Integer overflow in the index_urlfetch function in imap/index.c in Cyrus IMAP 2.3.19, 2.4.18, and 2.5.6 allows remote attackers to have unspecified impact via vectors related to urlfetch range checks. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The index_urlfetch function in index.c in Cyrus IMAP 2.3.x before 2.3.19, 2.4.x before 2.4.18, 2.5.x before 2.5.4 allows remote attackers to obtain sensitive information or possibly have unspecified. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.