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TI-2026-74364 Aliases CVE-2026-107350

PgBouncer authentication bypass lets attackers log in as other users

Priority MEDIUM 40CWE-287Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-287.

Summary

PgBouncer from 1.17.0 before 1.26.1 contains an improper authentication flaw (CWE-287). A remote attacker who knows the password of one user listed in auth_file can switch the login to a different user during SCRAM authentication. The attacker can then log in as any other SCRAM user, including PgBouncer admin users and backend superusers.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Improper authentication in PgBouncer 1.17.0 through 1.26.0 allows a remote attacker who knows the password of a user listed in auth_file to log in as any other user that authenticates using SCRAM, including PgBouncer admin users and backend superusers. A second StartupMessage sent during SCRAM authentication against a non-existent database is not rejected and switches the user being logged in as, while the SCRAM exchange is still verified against the keys of the first user.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00369 30th percentileScored 2026-11-07
Fix Fixed PgBouncer: 1.26.1Red Hat: 1 advisory

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—PgBouncer1.17.0 to before 1.26.11.26.1Patch availableCNA
  • PgBouncer Vendor— Affected 1.17.0 to before 1.26.1 Fixed in 1.26.1 Patch available CNA

Remediation

Upgrade PgBouncer to version 1.26.1. Red Hat fixes this in Red Hat Hardened Images through advisory RHSA-2026:83843.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA PgBouncer Fixed in 1.26.1

Red Hat 1 advisory

  • RHSA-2026:83843 Released 2026-10-16 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images pgbouncer-1.26.1-1.hum1@aarch64, pgbouncer-1.26.1-1.hum1@s390x, pgbouncer-1.26.1-1.hum1@src +1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    PgBouncer 1.26.1

    3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2026-74363 Infinite loop in PgBouncer startup options parameter handlingPriority LOW 39
    • TI-2026-74362 Integer overflow in PgBouncer buffer growth causes infinite loopPriority LOW 27
    Show all 3 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Hardened ImagesFixed RHSA-2026:83843

Timeline

  1. 2026-10-15 Threatist record created from CVE-2026-107350
  2. 2026-10-16 CISA SSVC decision points changed
  3. 2026-10-16 Priority changed: MEDIUM → LOW
  4. 2026-10-16 Priority changed: LOW → MEDIUM
  5. 2026-10-16 Affected versions changed · Red Hat
  6. 2026-10-16 CVSS score added · Red Hat
  7. 2026-10-18 Fix available: RHSA-2026:83843 · Red Hat
  8. 2026-10-18 Fix available: Red Hat Hardened Images · Red Hat

References

Other 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences