CVE catalog

CVE-2026-59969

Severity: Critical · CVSS 9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Published: Sep 16, 2026, 9:27:00 AM UTC
Updated: Sep 16, 2026, 10:16:51 AM UTC
Source: [NVD] · [CVE record]
EPSS: 0.33% · Oct 25, 2026

Apache ZooKeeper quorum TLS fails to enforce peer hostname verification in FIPS-mode deployments. When sslQuorum=true, zookeeper.fips-mode=true, ssl.quorum.hostnameVerification=true, and ssl.quorum.clientHostnameVerification=true are enabled, the Java SSLSocket quorum path accepts a CA-trusted peer certificate whose SAN does not match the connected host. A malicious or misissued peer certificate can therefore join quorum traffic, participate in leader election, and enter replication flows. Users are recommended to upgrade to version 3.8.7 or 3.9.6, which fixes the issue.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	zookeeper	sid	`3.9.6-2`	fixed
Debian	zookeeper	forky	`3.9.6-2`	fixed
Debian	zookeeper	trixie	`3.9.3-1+deb13u1`	vulnerable
Debian	zookeeper	bookworm	`3.8.0-11+deb12u2`	vulnerable
Debian	zookeeper	bookworm-security	`3.8.0-11+deb12u1`	vulnerable
Cpe	zookeeper	Not reported	`3.9.6`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	zookeeper	source	sid	`3.9.6-1`	not yet assigned	Not reported	Not reported
Debian	zookeeper	source	forky	`3.9.6-1`	not yet assigned	Not reported	Not reported
Debian	zookeeper	source	trixie	`(unfixed)`	not yet assigned	Not reported	Not reported
Debian	zookeeper	source	bookworm	`(unfixed)`	not yet assigned	Not reported	Not reported
Cpe	zookeeper	cpe	Not reported	`3.9.6`	Not reported	NVD-CVE-2026-59969	Not reported

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[libzookeeper-java]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · all · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · all · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · all · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · all · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[libzookeeper-java-doc]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · all · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · all · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · all · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · all · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[libzookeeper-mt2]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · amd64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · arm64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · amd64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · arm64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[libzookeeper-mt-dev]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · amd64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · arm64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · amd64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · arm64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[libzookeeper-st2]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · amd64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · arm64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · amd64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · arm64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[libzookeeper-st-dev]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · amd64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · arm64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · amd64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · arm64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[python3-zookeeper]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · amd64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · arm64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · amd64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · arm64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[zookeeper]Affected
Details (4)
- 3.8.0-11+deb12u2 · all · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · all · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · all · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · all · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[zookeeper-bin]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · amd64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · arm64 · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · amd64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · arm64 · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
[zookeeperd]Affected
Source package: [zookeeper]
Details (4)
- 3.8.0-11+deb12u2 · all · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u2 · all · bookworm
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · all · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12
- 3.8.0-11+deb12u1 · all · bookworm-security
  Affected
  nvd · zookeeper · debian · bookworm; nvd · zookeeper · debian · 12

[Debian 13 (Trixie)]

[libzookeeper-java]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · all · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · all · trixie
  Affected
  nvd · zookeeper · debian · 13
[libzookeeper-java-doc]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · all · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · all · trixie
  Affected
  nvd · zookeeper · debian · 13
[libzookeeper-mt2]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · amd64 · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · arm64 · trixie
  Affected
  nvd · zookeeper · debian · 13
[libzookeeper-mt-dev]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · amd64 · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · arm64 · trixie
  Affected
  nvd · zookeeper · debian · 13
[libzookeeper-st2]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · amd64 · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · arm64 · trixie
  Affected
  nvd · zookeeper · debian · 13
[libzookeeper-st-dev]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · amd64 · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · arm64 · trixie
  Affected
  nvd · zookeeper · debian · 13
[python3-zookeeper]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · amd64 · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · arm64 · trixie
  Affected
  nvd · zookeeper · debian · 13
[zookeeper]Affected
Details (2)
- 3.9.3-1+deb13u1 · all · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · all · trixie
  Affected
  nvd · zookeeper · debian · 13
[zookeeper-bin]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · amd64 · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · arm64 · trixie
  Affected
  nvd · zookeeper · debian · 13
[zookeeperd]Affected
Source package: [zookeeper]
Details (2)
- 3.9.3-1+deb13u1 · all · trixie
  Affected
  nvd · zookeeper · debian · 13
- 3.9.3-1+deb13u1 · all · trixie
  Affected
  nvd · zookeeper · debian · 13

Observed: Oct 23, 2026, 9:09:52 PM UTC

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]