CVE-2024-23185
published 2024-09-10CVE-2024-23185: Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when…
PriorityP339high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.28%
67.1th percentile
Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The full_value buffer has no size limit, so large headers can cause large memory usage. It doesn't matter whether it's a single long header line, or a single header split into multiple lines. This bug exists in all Dovecot versions. Incoming mails typically have some size limits set by MTA, so even largest possible header size may still fit into Dovecot's vsz_limit. So attackers probably can't DoS a victim user this way. A user could APPEND larger mails though, allowing them to DoS themselves (although maybe cause some memory issues for the backend in general). One can implement restrictions on headers on MTA component preceding Dovecot. No publicly available exploits are known.
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | dovecot | < dovecot 1:2.3.19.1+dfsg1-2.1+deb12u1 (bookworm) | dovecot 1:2.3.19.1+dfsg1-2.1+deb12u1 (bookworm) |
| dovecot | dovecot | >= 0 < 1:2.3.13+dfsg1-2+deb11u2 | 1:2.3.13+dfsg1-2+deb11u2 |
| dovecot | dovecot | >= 0 < 1:2.3.19.1+dfsg1-2.1+deb12u1 | 1:2.3.19.1+dfsg1-2.1+deb12u1 |
| dovecot | dovecot | >= 0 < 1:2.3.21.1+dfsg1-1 | 1:2.3.21.1+dfsg1-1 |
| dovecot | dovecot | >= 0 < 1:2.3.21.1+dfsg1-1 | 1:2.3.21.1+dfsg1-1 |
| dovecot | dovecot | >= 0 < 1:2.3.7.2-1ubuntu3.7 | 1:2.3.7.2-1ubuntu3.7 |
| dovecot | dovecot | >= 0 < 1:2.3.16+dfsg1-3ubuntu2.4 | 1:2.3.16+dfsg1-3ubuntu2.4 |
| dovecot | dovecot | >= 0 < 1:2.3.21+dfsg1-2ubuntu6 | 1:2.3.21+dfsg1-2ubuntu6 |
| open-xchange_gmbh | ox_dovecot_pro | <= 2.3.21 | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
vendor_ubuntu5.0MEDIUM
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
Ubuntu
Dovecot vulnerabilities
vendor_ubuntu·2024-09-16·CVSS 5.0
CVE-2024-23184 [MEDIUM] Dovecot vulnerabilities
Title: Dovecot vulnerabilities
Summary: Several security issues were fixed in Dovecot.
It was discovered that Dovecot incorrectly handled a large number of
address headers. A remote attacker could possibly use this issue to cause
Dovecot to consume resources, leading to a denial of service.
(CVE-2024-23184)
It was discovered that Dovecot incorrectly handled very large headers. A
remote attacker could possibly use this issue to cause Dovecot to consume
resources, leading to a denial of service. (CVE-2024-23185)
Instructions: In general, a standard system update will make all the necessary changes.
Ubuntu
Dovecot vulnerabilities
vendor_ubuntu·2024-09-02·CVSS 5.0
CVE-2024-23184 [MEDIUM] Dovecot vulnerabilities
Title: Dovecot vulnerabilities
Summary: Several security issues were fixed in Dovecot.
It was discovered that Dovecot did not not properly have restrictions on
ithe size of address headers. A remote attacker could possibly use this
issue to cause denial of service. (CVE-2024-23184, CVE-2024-23185)
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
dovecot: very large headers can cause resource exhaustion when parsing message
vendor_redhat·2024-08-15·CVSS 7.5
CVE-2024-23185 [HIGH] CWE-770 dovecot: very large headers can cause resource exhaustion when parsing message
dovecot: very large headers can cause resource exhaustion when parsing message
Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The full_value buffer has no size limit, so large headers can cause large memory usage. It doesn't matter whether it's a single long header line, or a single header split into multiple lines. This bug exists in all Dovecot versions. Incoming mails typically have some size limits set by MTA, so even largest possible header size may still fit into Dovecot's vsz_limit. So attackers probably can't DoS a victim user this way. A user could APPEND larger
Debian
CVE-2024-23185: dovecot - Very large headers can cause resource exhaustion when parsing message. The messa...
vendor_debian·2024·CVSS 7.5
CVE-2024-23185 [HIGH] CVE-2024-23185: dovecot - Very large headers can cause resource exhaustion when parsing message. The messa...
Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The full_value buffer has no size limit, so large headers can cause large memory usage. It doesn't matter whether it's a single long header line, or a single header split into multiple lines. This bug exists in all Dovecot versions. Incoming mails typically have some size limits set by MTA, so even largest possible header size may still fit into Dovecot's vsz_limit. So attackers probably can't DoS a victim user this way. A user could APPEND larger mails though, allowing them to DoS themselves (although maybe cause some memory
OSV
dovecot vulnerabilities
osv·2024-09-16·CVSS 5.0
CVE-2024-23184 [MEDIUM] dovecot vulnerabilities
dovecot vulnerabilities
It was discovered that Dovecot incorrectly handled a large number of
address headers. A remote attacker could possibly use this issue to cause
Dovecot to consume resources, leading to a denial of service.
(CVE-2024-23184)
It was discovered that Dovecot incorrectly handled very large headers. A
remote attacker could possibly use this issue to cause Dovecot to consume
resources, leading to a denial of service. (CVE-2024-23185)
GHSA
GHSA-g9m4-c8qf-67qw: Very large headers can cause resource exhaustion when parsing message
ghsa_unreviewed·2024-09-10
CVE-2024-23185 [HIGH] CWE-770 GHSA-g9m4-c8qf-67qw: Very large headers can cause resource exhaustion when parsing message
Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The full_value buffer has no size limit, so large headers can cause large memory usage. It doesn't matter whether it's a single long header line, or a single header split into multiple lines. This bug exists in all Dovecot versions. Incoming mails typically have some size limits set by MTA, so even largest possible header size may still fit into Dovecot's vsz_limit. So attackers probably can't DoS a victim user this way. A user could APPEND larger mails though, allowing them to DoS themselves (although maybe cause some memory
OSV
CVE-2024-23185: Very large headers can cause resource exhaustion when parsing message
osv·2024-09-10·CVSS 7.5
CVE-2024-23185 [HIGH] CVE-2024-23185: Very large headers can cause resource exhaustion when parsing message
Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The full_value buffer has no size limit, so large headers can cause large memory usage. It doesn't matter whether it's a single long header line, or a single header split into multiple lines. This bug exists in all Dovecot versions. Incoming mails typically have some size limits set by MTA, so even largest possible header size may still fit into Dovecot's vsz_limit. So attackers probably can't DoS a victim user this way. A user could APPEND larger mails though, allowing them to DoS themselves (although maybe cause some memory
OSV
dovecot vulnerabilities
osv·2024-09-02·CVSS 5.0
CVE-2024-23184 [MEDIUM] dovecot vulnerabilities
dovecot vulnerabilities
It was discovered that Dovecot did not not properly have restrictions on
ithe size of address headers. A remote attacker could possibly use this
issue to cause denial of service. (CVE-2024-23184, CVE-2024-23185)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2024-09-10
Published