GHSA-xr7v-hj32-mr4r · Severity: high — Attacker can send a specifically crafted message before authentication that causes managesieve to...
Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. No publicly available exploits are known.
Conclusion & alert: CVE-2026-27858 is rated Moderate Risk (48.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.79%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-30 | 0.46% | 0.79% | +0.33% |
| 2 | 2026-06-15 | 0.02% | 0.46% | +0.43% |
| 3 | 2026-04-30 | — | 0.02% | — |
Full EPSS history (5 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c |
GHSA-xr7v-hj32-mr4r · Severity: high — Attacker can send a specifically crafted message before authentication that causes managesieve to...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-27858 not yet assigned priority: Debian including 1 source packages (dovecot), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2026-27858 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2026-27858 |
suse
|
high | CVE-2026-27858 severity important: SUSE including 9 source package names (dovecot, dovecot24-2.4.3-1.1, …), 29 product×package rows across 22 product lines (SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS, … (22 product lines)): Known Not Affected 21, Fixed 8. | https://www.suse.com/security/cve/CVE-2026-27858/ |
ubuntu
|
medium | CVE-2026-27858 medium priority: Ubuntu including 1 source packages (dovecot), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): needed 4, released 4. | https://ubuntu.com/security/CVE-2026-27858 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| dovecot | dovecot | < 2.4.3 | cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:* |
| open-xchange | dovecot | < 2.3.22.1 | cpe:2.3:a:open-xchange:dovecot:*:*:*:*:pro:*:*:* |
| open-xchange | dovecot | >= 3.0.0, < 3.0.5 | cpe:2.3:a:open-xchange:dovecot:*:*:*:*:pro:*:*:* |
| open-xchange | dovecot | >= 3.1.0, < 3.1.4 | cpe:2.3:a:open-xchange:dovecot:*:*:*:*:pro:*:*:* |