CVE-2026-19538
published 2026-08-26CVE-2026-19538: The BLOCKED access control list items that are evaluated to deny access on the the proxy protocol port can be bypassed completely when connecting over TCP or…
PriorityP346high7.5CVSS 3.1
AVNACLPRNUINSUCNIHAN
EPSS
0.30%
23.1th percentile
The BLOCKED access control list items that are evaluated to deny access on the the proxy protocol port can be bypassed completely when connecting over TCP or TLS and sending the query twice on connection that is kept open.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| nlnet_labs | nsd | >= 4.8.0 < 4.15.1 | 4.15.1 |
| nlnetlabs | nsd | >= 4.8.0 < 4.15.1 | 4.15.1 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
nvdv4.08.2HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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Bugzilla
CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port
bugzilla·2026-08-26·CVSS 8.2
CVE-2026-19538 [HIGH] CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port
CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port
The BLOCKED access control list items that are evaluated to deny access on the the proxy protocol port can be bypassed completely when connecting over TCP or TLS and sending the query twice on connection that is kept open.
Bugzilla
CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port [fedora-all]
bugzilla·2026-08-26·CVSS 8.2
CVE-2026-19538 [HIGH] CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port [fedora-all]
CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The BLOCKED access control list items that are evaluated to deny access on the the proxy protocol port can be bypassed completely when connecting over TCP or TLS and sending the query twice on connection that is kept open.
Bugzilla
CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port [epel-all]
bugzilla·2026-08-26·CVSS 8.2
CVE-2026-19538 [HIGH] CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port [epel-all]
CVE-2026-19538 nsd: nsd: Access control bypass via repeated queries on proxy protocol port [epel-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The BLOCKED access control list items that are evaluated to deny access on the the proxy protocol port can be bypassed completely when connecting over TCP or TLS and sending the query twice on connection that is kept open.
2026-08-26
Published