CVE-2026-42006 (GCVE-0-2026-42006)

Vulnerability from cvelistv5 – Published: 2026-05-12 13:28 – Updated: 2026-07-24 12:05
VLAI
Summary
An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. The fix in CVE-2026-27857 was incomplete, only blocking one way of doing this, so there was still another way left open. In particular, the fix was for closing braces, but you could still use open braces to bypass the limit. Using excessive bracing, attacker can cause memory usage up to configured memory limit. Install fixed version, or configure vsz_limit for imap process to low value. No publicly available exploits are known.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
OX
References
Impacted products
Vendor Product Version
Open-Xchange GmbH OX Dovecot Pro Affected: 0 , ≤ 3.0.5 (semver)
Affected: 0 , ≤ 3.1.4 (semver)
Affected: 0 , ≤ 2.4.3 (semver)
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Red Hat Red Hat Enterprise Linux 10 Unaffected: 1:2.3.21-19.el10_2.1 , < * (rpm)
    cpe:/o:redhat:enterprise_linux:10.2
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Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support Unaffected: 1:2.3.21-16.el10_0.2 , < * (rpm)
    cpe:/o:redhat:enterprise_linux_eus:10.0
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Red Hat Red Hat Enterprise Linux 9 Unaffected: 1:2.3.16-18.el9_8.1 , < * (rpm)
    cpe:/a:redhat:enterprise_linux:9
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Red Hat Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions Unaffected: 1:2.3.16-8.el9_2.3 , < * (rpm)
    cpe:/a:redhat:rhel_e4s:9.2
 Create a notification for this product.
Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions Unaffected: 1:2.3.16-11.el9_4.3 , < * (rpm)
    cpe:/a:redhat:rhel_e4s:9.4
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Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support Unaffected: 1:2.3.16-15.el9_6.2 , < * (rpm)
    cpe:/a:redhat:rhel_eus:9.6
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Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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Red Hat Red Hat Enterprise Linux 8     cpe:/o:redhat:enterprise_linux:8
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      "source": "Red Hat CSAF VEX",
      "status": "final",
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      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.