High severity · published Nov 22, 2021
CVE-2021-3935
When PgBouncer is configured to use "cert" authentication, a man-in-the-middle attacker can inject arbitrary SQL queries when a connection is first established, despite the use of…
8.1
CVSS
1.1%
EPSS
No
On KEV
Description
When PgBouncer is configured to use "cert" authentication, a man-in-the-middle attacker can inject arbitrary SQL queries when a connection is first established, despite the use of TLS certificate verification and encryption. This flaw affects PgBouncer versions prior to 1.16.1.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 66% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0 · source: NVD
EL
Enterprise Linux · Redhat
7.0 · source: NVD
FE
Fedora · Fedoraproject
35 · source: NVD
PG
Pgbouncer · Pgbouncer
before 1.16.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3935
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3935
Release Notes
http://www.pgbouncer.org/changelog.html#pgbouncer-116x
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2021251
Mailing List
https://lists.debian.org/debian-lts-announce/2022/02/msg00016.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNPCV3KRDI5PLLLKADFVIOHACQJLZMLI/
lists.debian.org
https://lists.debian.org/debian-lts-announce/2025/05/msg00032.html
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