CVE detail
CVE-2026-27857
Sending "NOOP (((...)))" command with 4000 parenthesis open+close results in ~1MB extra memory usage. Longer commands will result in client disconnection. This 1 MB can be left allocated for longer time periods by not sending the command ending LF. So attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Install fixed version, there is no other remediation. No publicly available exploits are known.
Buzz score
Why this CVE is surfacing
This all-time snapshot uses the same composite formula as Trending across a 30-year evidence window, rather than a current rolling window.
Buzz score components · mention 29.4 · diversity 13.0 · KEV 0.0 · OTX 0.0 · PoC 0.0
Why it matters now
Mention timeline
- Total mentions
- 0
- within the 30d window
- Peak daily
- 0
- highest bucket
Evidence
Source links by recency
18 source links · newest first
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27857.jsonsecurity.access.redhat.com
No excerpt available.
Vendor Advisorysecurity.access.redhat.comMar 27, 2026, 9:16 AM - https://bugzilla.redhat.com/show_bug.cgi?id=2452179bugzilla.redhat.com
No excerpt available.
Exploitbugzilla.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/security/cve/CVE-2026-27857access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:26564access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:19455access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:19453access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:19364access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:19149access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:18053access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:17630access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:17628access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:17626access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:17625access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:17602access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:13857access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:13830access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://access.redhat.com/errata/RHSA-2026:13498access.redhat.com
No excerpt available.
Vendor Advisoryaccess.redhat.comMar 27, 2026, 9:16 AM - https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.jsondocumentation.open-xchange.com
No excerpt available.
Vendor Advisorydocumentation.open-xchange.comMar 27, 2026, 9:16 AM
Exploit code
Public exploit repository references
Public PoC repositories are third-party, potentially unsafe artifacts. Treat their code as untrusted and use it only on authorized systems in an isolated, least-privilege environment. cvebuzz does not execute the code or verify that an exploit works.
0 repository references · best confidence N/A · max 0 stars
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