CVE-2026-107348
Integer overflow causes an infinite loop in message buffer growth in PgBouncer
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- 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
5.9
Integer overflow causes an infinite loop in message buffer growth in PgBouncer
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
- Record
CVE-2026-107348- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-190, CWE-835
- Updated
- 2026-11-02
EUVDEUVD-2026-101498
5.9
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
- Record
EUVD-2026-101498- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-982p-g5h4-w372
5.9
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through...
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
- Record
GHSA-982p-g5h4-w372- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-190
- Updated
- 2026-11-02
NVD
5.9
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
- Record
CVE-2026-107348- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-190, CWE-835
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-107348
5.9
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
- Record
DEBIAN-CVE-2026-107348- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVRHSA-2026:83843
8.8
Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update
- Record
RHSA-2026:83843- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-107348
5.9
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
- Record
UBUNTU-CVE-2026-107348- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVAZL-108195 No score
CVE-2026-107348 affecting package pgbouncer for versions less than 1.26.1-1
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
- Record
AZL-108195- Updated
- 2026-11-02
OSVBIT-pgbouncer-2026-107348 No score
Integer overflow causes an infinite loop in message buffer growth in PgBouncer
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
- Record
BIT-pgbouncer-2026-107348- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
pgbouncerAzure Linux:3 |
before 1.26.1-1 | 1.26.1-1 |
pgbouncerBitnami |
1.21.0 up to 1.26.1 | 1.26.1 |
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 20 moreShow less1.20.1-11.21.0-11.22.0-11.22.1-11.23.0-11.23.1-11.24.0-21.24.0-31.24.1-11.25.0-11.25.0-21.25.1-11.25.2-11.26.0-11.26.0-21.26.0-31.26.0-41.26.0-51.26.0-61.26.1-1 |
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 9 moreShow less1.25.1-11.25.2-11.26.0-11.26.0-21.26.0-31.26.0-41.26.0-51.26.0-61.26.1-1 |
None known |
pgbouncerDebian:14 |
before 1.26.1-1, plus listed versions 1.24.1-11.25.0-11.25.0-21.25.1-11.25.2-1 Show 6 moreShow less1.26.0-11.26.0-21.26.0-31.26.0-41.26.0-51.26.0-6 |
1.26.1-1 |
pgbouncerRed Hat:hummingbird:1 From an advisory covering 3 CVEs |
before 0:1.26.1-1.hum1 | 0:1.26.1-1.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-2026-107348 is a medium vulnerability (CVSS 5.9) in pgbouncer, published October 14, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.39%, the 33rd percentile. Fixed in pgbouncer 1.26.1-1.
References
pgbouncer.org/changelog.html
nvd.nist.gov/vuln/detail/CVE-2026-107348
github.com/advisories/GHSA-982p-g5h4-w372
security-tracker.debian.org/tracker/CVE-2026-107348
access.redhat.com/errata/RHSA-2026:83843
images.redhat.com
Show 14 moreShow less
access.redhat.com/security/cve/CVE-2026-107348
access.redhat.com/security/updates/classification
access.redhat.com/security/cve/CVE-2026-107349
access.redhat.com/security/cve/CVE-2026-107350
security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_83843.json
bugzilla.redhat.com/show_bug.cgi?id=2552741
cve.org/CVERecord?id=CVE-2026-107348
bugzilla.redhat.com/show_bug.cgi?id=2552735
cve.org/CVERecord?id=CVE-2026-107349
nvd.nist.gov/vuln/detail/CVE-2026-107349
bugzilla.redhat.com/show_bug.cgi?id=2552733
cve.org/CVERecord?id=CVE-2026-107350
nvd.nist.gov/vuln/detail/CVE-2026-107350
ubuntu.com/security/CVE-2026-107348