CVE-2026-6668
Integer overflow causes an infinite loop in packet buffer growth in PgBouncer
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.5
Integer overflow causes an infinite loop in packet buffer growth in PgBouncer
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
- Record
CVE-2026-6668- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-190, CWE-835
- Updated
- 2026-11-02
EUVDEUVD-2026-85363
7.5
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
- Record
EUVD-2026-85363- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-r96c-7w9v-wrc8
7.5
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an...
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
- Record
GHSA-r96c-7w9v-wrc8- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-190
- Updated
- 2026-11-02
NVD
7.5
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
- Record
CVE-2026-6668- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-190, CWE-835
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-6668
7.5
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
- Record
DEBIAN-CVE-2026-6668- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVRHSA-2026:70698
7.5
Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update
- Record
RHSA-2026:70698- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-6668
7.5
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
- Record
UBUNTU-CVE-2026-6668- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVAZL-103433 No score
CVE-2026-6668 affecting package pgbouncer for versions less than 1.26.0-1
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
- Record
AZL-103433- Updated
- 2026-11-02
OSVBIT-pgbouncer-2026-6668 No score
Integer overflow causes an infinite loop in packet buffer growth in PgBouncer
Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.
- Record
BIT-pgbouncer-2026-6668- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
pgbouncerAzure Linux:3 |
before 1.26.0-1 | 1.26.0-1 |
pgbouncerBitnami |
before 1.26.0 | 1.26.0 |
pgbouncerDebian:12 |
All versions, plus listed versions 1.18.0-11.18.0-1+deb12u11.19.0-11.19.1-11.20.0-1 Show 19 moreShow less1.20.1-11.21.0-11.22.0-11.22.1-11.23.0-11.23.1-11.24.0-21.24.0-31.24.1-11.25.0-11.25.0-21.25.1-11.25.2-11.26.0-11.26.0-21.26.0-31.26.0-41.26.0-51.26.0-6 |
None known |
pgbouncerDebian:13 |
All versions, plus listed versions 1.24.1-11.24.1-1+deb13u11.24.1-1+deb13u21.25.0-11.25.0-2 Show 8 moreShow less1.25.1-11.25.2-11.26.0-11.26.0-21.26.0-31.26.0-41.26.0-51.26.0-6 |
None known |
pgbouncerDebian:14 |
before 1.26.0-1, plus listed versions 1.24.1-11.25.0-11.25.0-21.25.1-11.25.2-1 |
1.26.0-1 |
pgbouncerRed Hat:hummingbird:1 From an advisory covering 3 CVEs |
before 0:1.26.0-0.1.hum1 | 0:1.26.0-0.1.hum1 |
pgbouncerUbuntu:16.04:LTS |
All versions, plus listed versions 1.5.5-11.6.1-11.7-1 |
None known |
pgbouncerUbuntu:18.04:LTS |
All versions, plus listed versions 1.7.2-3build11.7.2-65-g2b8e6cf-11.8.1-11.8.1-1build1 |
None known |
pgbouncerUbuntu:20.04:LTS |
All versions, plus listed versions 1.10.0-11.10.0-1build11.11.0-11.12.0-21.12.0-3 |
None known |
pgbouncerUbuntu:22.04:LTS |
All versions, plus listed versions 1.15.0-11.16.1-1ubuntu1 |
None known |
pgbouncerUbuntu:24.04:LTS |
All versions, plus listed versions 1.20.0-11.21.0-11.22.0-11.22.0-1build11.22.0-1build31.22.0-1build4 |
None known |
pgbouncerUbuntu:26.10 |
All versions, plus listed versions 1.25.1-11.25.2-11.25.2-1ubuntu1 |
None known |
pgbouncerUbuntu:26.04:LTS |
All versions, plus listed versions 1.24.1-11.25.0-21.25.1-1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-6668 is a high vulnerability (CVSS 7.5) in pgbouncer, published September 23, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.57%, the 47th percentile. Fixed in pgbouncer 1.26.0-1.
References
pgbouncer.org/changelog.html
nvd.nist.gov/vuln/detail/CVE-2026-6668
github.com/advisories/GHSA-r96c-7w9v-wrc8
security-tracker.debian.org/tracker/CVE-2026-6668
access.redhat.com/errata/RHSA-2026:70698
images.redhat.com
Show 14 moreShow less
access.redhat.com/security/cve/CVE-2026-6668
access.redhat.com/security/updates/classification
access.redhat.com/security/cve/CVE-2026-6669
access.redhat.com/security/cve/CVE-2026-19888
security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_70698.json
bugzilla.redhat.com/show_bug.cgi?id=2539548
cve.org/CVERecord?id=CVE-2026-6668
bugzilla.redhat.com/show_bug.cgi?id=2539546
cve.org/CVERecord?id=CVE-2026-6669
nvd.nist.gov/vuln/detail/CVE-2026-6669
bugzilla.redhat.com/show_bug.cgi?id=2539545
cve.org/CVERecord?id=CVE-2026-19888
nvd.nist.gov/vuln/detail/CVE-2026-19888
ubuntu.com/security/CVE-2026-6668