A flaw was found in dovecot 2.0 up to 2.2.33 and 2.3.0.
Noroxi assessment
Priority: Monitor (action score 31/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 3.1% (FIRST EPSS); higher than 87.4% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: dovecot (Alpine:v3.10) 2.3.1-r0; dovecot (Alpine:v3.7) 2.2.34-r0; dovecot (Debian:12) 1:2.2.34-1.
Low priority for now. Upgrade to dovecot (Alpine:v3.10) 2.3.1-r0; dovecot (Alpine:v3.7) 2.2.34-r0; dovecot (Debian:12) 1:2.2.34-1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
Follow it and we'll tell you in the daily email digest when the record enters KEV, gets exploit code, is updated (including a fix) or its EPSS rises 20 points in a week. Connect a webhook and KEV listings and weaponized exploits arrive instantly.
Is your version affected? Check itA flaw was found in dovecot 2.0 up to 2.2.33 and 2.3.0. An abort of SASL authentication results in a memory leak in dovecot's auth client used by login processes. The leak has impact in high performance configuration where same login processes are reused and can cause the process to crash due to memory exhaustion.
- Published
- Jan 25, 2018
- Updated
- Jun 16, 2026
- EPSS
- 3.1% · 87th percentile
- CWE
- CWE-400
Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 3.1%
Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| dovecot | dovecot | cpe:2.3:a:dovecot:dovecot |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
Using dovecot? Add it to your stack and be the first to know about CVEs like this one. (Email server)
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- dovecot dovecot2.0.0 and later · up to 2.2.33 inclusive
- dovecot dovecot2.3.0
Versions reported by the vendor
Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.
The Dovecot Project dovecot
- 2.0 up to 2.2.33 and 2.3.0affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Alpine:v3.10 | dovecot | from 2.0.0 · before 2.3.1-r0 | 2.3.1-r0 |
| Alpine:v3.7 | dovecot | from 2.0.0 · before 2.2.34-r0 | 2.2.34-r0 |
| Debian:12 | dovecot | before 1:2.2.34-1 | 1:2.2.34-1 |
| Debian:7 | dovecot | before 1:2.1.7-7+deb7u2 | 1:2.1.7-7+deb7u2 |
| Debian:8 | dovecot | before 1:2.2.13-12~deb8u4 | 1:2.2.13-12~deb8u4 |
| Debian:9 | dovecot | before 1:2.2.27-3+deb9u2 | 1:2.2.27-3+deb9u2 |
| openSUSE:Tumbleweed | dovecot23 | before 2.3.16-1.6 | 2.3.16-1.6 |
| openSUSE:Tumbleweed | dovecot24 | before 2.4.0-1.1 | 2.4.0-1.1 |
| SUSE:Linux Enterprise Server for Raspberry Pi 12 SP2 | dovecot22 | before 2.2.31-19.5.1 | 2.2.31-19.5.1 |
Same product
dovecot: all recordsOther highest-scoring records for the same primary product.
- CVE-2019-11500In Dovecot before 2.2.36.4 and 2.3.x before 2.3.7.2 (and Pigeonhole before 0.5.7.2), protocol processing can fail for quoted strings.58Plan
- CVE-2020-7046lib-smtp in submission-login and lmtp in Dovecot 2.3.9 before 2.3.9.3 mishandles truncated UTF-8 data in command parameters, as demonstrated45Plan
- CVE-2016-8652The auth component in Dovecot before 2.2.27, when auth-policy is configured, allows a remote attackers to cause a denial of service (crash) 37Monitor
- CVE-2026-27851When safe filter is used with variable expansion, all following pipelines on the same string are incorrectly interpreted as safe too, enabli36Monitor
- CVE-2022-30550An issue was discovered in the auth component in Dovecot 2.2 and 2.3 before 2.3.20.36Monitor
- CVE-2017-14461A specially crafted email delivered over SMTP and passed on to Dovecot by MTA can trigger an out of bounds read resulting in potential sensi33Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| alpine:dovecot | 2.3.1-r0 · Alpine:v3.10 | Package registry (OSV) |
| debian:dovecot | 1:2.2.34-1 · Debian:12 | Package registry (OSV) |
| opensuse:dovecot23 | 2.3.16-1.6 · openSUSE:Tumbleweed | Package registry (OSV) |
| opensuse:dovecot24 | 2.4.0-1.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| suse:dovecot22 | 2.2.31-19.5.1 · SUSE:Linux Enterprise Server for Raspberry Pi 12 SP2 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-400 · Uncontrolled Resource ConsumptionCVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Root cause
Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.
The bug in code
The whole CWE-400 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
function expand(node) { return node.children.map(expand);}Fixed
const MAX_DEPTH = 32;function expand(node, depth = 0) { if (depth > MAX_DEPTH) throw new Error("too deep"); return node.children.map((c) => expand(c, depth + 1));}Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- bugzilla.redhat.com/show_bug.cgi?id=1532768
- github.com/dovecot/core/commit/1a29ed2f96da1be22fa5a4d96c7583aa81b8b060.patch
- lists.debian.org/debian-lts-announce/2018/03/msg00036.html
- usn.ubuntu.com/3556-1/
- usn.ubuntu.com/3556-2/
- www.debian.org/security/2018/dsa-4130
- www.dovecot.org/list/dovecot-news/2018-February/000370.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.