High severity · published Sep 23, 2026
CVE-2026-6668
Integer overflow causes an infinite loop in packet buffer growth in PgBouncer
7.5
CVSS
0.6%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PG
PgBouncer ·
through 1.25.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-6668
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-6668
www.pgbouncer.org
https://www.pgbouncer.org/changelog.html
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