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CVE-2019-11500

67
FAUCET Score

CVE-2019-11500 is a critical vulnerability affecting Dovecot versions prior to 2.2.36.4 and 2.3.7.2, and Pigeonhole before 0.5.7.2, as well as Debian and FedoraProject distributions. It stems from mishandling of null characters in quoted strings during protocol processing, leading to out-of-bounds writes. This flaw carries a CVSS score of 9.8 (Critical) due to its network-based attack vector, low attack complexity, and potential for remote code execution, compromising confidentiality, integrity, and availability. While there is no evidence of active exploitation (KEV) or public exploit code (Metasploit, Nuclei, ExploitDB), the vulnerability has garnered significant community discussion, indicating awareness and potential for future exploitation.

Impacted Technologies

VendorProductVersion(s)CPE
< 2.2.36.4CPE matchmatch criteria
cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:*
>= 2.3.0, < 2.3.7.2CPE matchmatch criteria
cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:*
< 0.5.7.2CPE matchmatch criteria
cpe:2.3:a:dovecot:pigeonhole:*:*:*:*:*:*:*:*
8.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
30CPE matchmatch criteria
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.0

9.8CRITICAL

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
5.9
CvssVersion
3.0

Exploit Intelligence

EPSS Score
62.58%
Probability of exploitation in next 30 days
EPSS Percentile
99.1%
Percentile rank of EPSS score among Peer Group
As of 2026-07-26
Model: v2026.06.15
This CVE's current EPSS score of 0.6258 is in the 97th percentile among its peer group of 36,833 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (10)

denopatch availablevia llm_extracted
View patch
drupalpatch availablevia llm_extracted
View patch
freeswitchpatch availablevia llm_extracted
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 7Fixed in: dovecot-1:2.2.36-3.el7_7.1
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 8Fixed in: dovecot-1:2.2.36-5.el8_0.1
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 6Fixed in: dovecot-1:2.0.9-22.el6_10.1
View patch
synologypatch availablevia llm_extracted
Fixed in: null
View patch
boschvendor investigatingvia llm_extracted
View patch
broadcomvendor investigatingvia llm_extracted
View patch
ubiquitivendor investigatingvia llm_extracted
View patch

Vendor Advisories (8)

redhatCVE-2019-11500Important

dovecot: improper NULL byte handling in IMAP and ManageSieve protocol parsers leads to out of bounds writes

Aug 28, 2019
drupalllm-drupal-9825d58694262279

IMAP and ManageSieve protocol parsers do not properly handle NUL byte when scanning data in quoted strings

Aug 28, 2019
ubiquitillm-ubiquiti-5a6a68e51236a1e1

IMAP and ManageSieve protocol parsers do not properly handle NUL byte when scanning data in quoted strings

Aug 28, 2019
synologyllm-synology-fbfb6746e237777a

IMAP and ManageSieve protocol parsers do not properly handle NUL byte when scanning data in quoted strings

Aug 28, 2019
denollm-deno-0547b6ed0d7e2507

IMAP and ManageSieve protocol parsers do not properly handle NUL byte when scanning data in quoted strings

Aug 28, 2019
broadcomllm-broadcom-f458ca2473662f61

CVE-2019-11500: IMAP and ManageSieve protocol parsers do not properly handle NUL byte when scanning data in quoted strings

Aug 28, 2019
freeswitchllm-freeswitch-726c4a2a0f637f66

IMAP and ManageSieve protocol parsers do not properly handle NUL byte when scanning data in quoted strings

Aug 28, 2019
boschllm-bosch-4ce3ac92501ce011

CVE-2019-11500: IMAP and ManageSieve protocol parsers do not properly handle NUL byte when scanning data in quoted strings

Aug 28, 2019

References

lists.opensuse.org / opensuse-security-announce/2019-10/msg00024.html
lists.opensuse.org / opensuse-security-announce/2019-10/msg00026.html
access.redhat.com / errata/RHSA-2019:2822
access.redhat.com / errata/RHSA-2019:2836
access.redhat.com / errata/RHSA-2019:2885
dovecot.org / pipermail/dovecot-news/2019-August/000417.html
PatchVendor Advisory
lists.debian.org / debian-lts-announce/2019/08/msg00035.html
Mailing ListThird Party Advisory
lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/3GYTZLLDNIFWT7D7JSB25ERJNMOR4CQ3
lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/KVHY3MU2OK2EWZJFGNDSAOMD42L7DFPX
lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/YSJVVVRAE3SITC2ZLGCPMFDN3WVYZBWF
security.gentoo.org / glsa/201908-29
Third Party Advisory
dovecot.org / security.html
Vendor Advisory
openwall.com / lists/oss-security/2019/08/28/3
ExploitMailing ListThird Party Advisory