{"id":"CVE-2026-6668","state":"PUBLISHED","title":"Integer overflow causes an infinite loop in packet buffer growth in PgBouncer","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.","publishedAt":"2026-09-23T16:04:47.158Z","updatedAt":"2026-09-23T16:46:13.834Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"PostgreSQL"},"assigner":"PostgreSQL","products":["n/a PgBouncer"],"affected":[{"vendor":"n/a","product":"PgBouncer","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"1.25.2","versionType":"semver"}]}],"references":["https://www.pgbouncer.org/changelog.html"],"weaknesses":["CWE-190","CWE-835"],"ingestedAt":"2026-10-29T20:12:49.727Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/6xxx/CVE-2026-6668.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-6668","state":"PUBLISHED","datePublished":"2026-09-23T16:04:47.158Z","dateUpdated":"2026-09-23T16:46:13.834Z","assignerShortName":"PostgreSQL","assignerOrgId":"f86ef6dc-4d3a-42ad-8f28-e6d5547a5007","dateReserved":"2026-04-20T12:25:46.351Z"},"containers":{"cna":{"title":"Integer overflow causes an infinite loop in packet buffer growth in PgBouncer","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"n/a","product":"PgBouncer","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"1.25.2","versionType":"semver"}]}],"references":[{"url":"https://www.pgbouncer.org/changelog.html"}],"metrics":[{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-190","lang":"en","type":"CWE","description":"Integer Overflow or Wraparound"}]},{"descriptions":[{"cweId":"CWE-835","lang":"en","type":"CWE","description":"Loop with Unreachable Exit Condition ('Infinite Loop')"}]}],"providerMetadata":{"shortName":"PostgreSQL","orgId":"f86ef6dc-4d3a-42ad-8f28-e6d5547a5007","dateUpdated":"2026-09-23T16:04:47.158Z"},"configurations":[{"lang":"en","value":"max_packet_size is left at its default of 2147483647 (default configuration), which is what permits a packet large enough to reach the overflow. No other non-default configuration is required."}],"workarounds":[{"lang":"en","value":"Set max_packet_size well below 1073741824 so that no single packet can grow a packet buffer past the overflow threshold"}],"credits":[{"lang":"en","value":"Thanks to @var77 for finding and reporting this issue.","type":"finder"}]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-6668","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-09-23T16:33:22.320321Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-23T16:46:13.834Z"}}]}}}