PostgreSQL Anonymizer contains a vulnerability that allows unprivileged masked users to repeatedly call the anon.hash() function and collects (seed, hashoutput) pairs to perform an offline brute-force attack and deduce the salt. A masked role can run a RESTRICTED function when the call is placed inside the sub-select. The problem is resolved in PostgreSQL Anonymizer 3.2.3 and later versions

pgpartman is a PostgreSQL extension that manages partitioned tables by time or ID. Prior to 5.5.0, when pgjobmon is installed and partconfig.jobmon is true, exception handlers in multiple pgpartman functions place pparenttable verbatim inside a SQL string literal used to call pgjobmon.addjob(). A partmanuser can create a parent-table name containing a single quote that terminates the literal and injects SQL when an affected exception path runs. If pgpartmanbgw reaches that path, the injected SQL executes with pgpartmanbgw.role privileges, which default to PostgreSQL superuser, permitting database-wide compromise and operating-system command execution as the PostgreSQL service account. The persistent partconfig row can trigger the escalation again on later maintenance ticks. This issue is fixed in version 5.5.0.

Summary pgjdbc is vulnerable to a client-side denial of service during SCRAM-SHA-256 authentication.

Impact A malicious server can instruct the driver to perform SCRAM authentication with a very large iteration count. With a large enough value, the client spends an unbounded amount of CPU time inside PBKDF2 before authentication can fail. A single attempt ties up a CPU core. Repeated or concurrent attempts exhaust client CPU and can wedge connection pools.

In affected versions, loginTimeout did not fully mitigate this problem. When loginTimeout expired, the caller could stop waiting, but the worker thread performing the connection attempt could continue running and burning CPU inside the SCRAM PBKDF2 computation.

This issue affects availability. It does not provide authentication bypass, privilege escalation, or direct password disclosure.

A user is vulnerable when all of the following are true:

1. The connection uses SCRAM-SHA-256 authentication. 2. The client reaches a malicious, compromised, or attacker-controlled PostgreSQL endpoint. 3. That endpoint sends a very large SCRAM PBKDF2 iteration count in the server-first-message.

In practice, that can happen in these situations:

- the application lets end users or tenants supply their own database connection details (as in many BI, reporting, analytics, ETL, and low-code platforms), so a user can point the shared client host at a server they control - the application accepts connection strings, hostnames, or JDBC URLs from user input, configuration uploaded by users, or other untrusted sources - the application is configured to connect to a PostgreSQL server that is itself malicious or later becomes compromised - the application connects through an untrusted proxy, relay, tunnel, bastion, or connection-pooling service that can act as the PostgreSQL server - an attacker can redirect the client to a fake PostgreSQL endpoint by manipulating DNS, service discovery, Kubernetes service resolution, /etc/hosts, environment variables, or similar indirection - an active network attacker on the path can impersonate the server because the connection does not strongly verify server identity (for example, sslmode lower than verify-full, or trusting a CA that signs hosts outside the operator's control)

The issue is more damaging when the application uses connection retries, many parallel connection attempts, or loginTimeout and assumes the timeout fully stops the work.

Patches The patch introduces a new connection property, scramMaxIterations, with a default of 100K. The client now rejects SCRAM server messages that advertise more PBKDF2 iterations than the configured cap before starting the PBKDF2 computation begins.

Workarounds

Until a patched version of pgjdbc is deployed, the following measures reduce exposure:

1. Only connect to trusted PostgreSQL servers whose identity is verified. Connect only to trusted PostgreSQL servers, and verify server identity with TLS using sslmode=verify-full and a trusted CA. TLS without certificate and hostname verification is not sufficient as an active network attacker can still impersonate the server.

2. Do not rely on loginTimeout as a complete mitigation on unpatched versions. On affected versions, loginTimeout can stop the waiting caller while the worker thread continues spending CPU.

3. Avoid SCRAM on untrusted or interceptable connection paths. For those paths, use an authentication method that does not let the server choose a SCRAM PBKDF2 iteration count.

4. Reduce blast radius operationally. Limit parallel connection attempts, add retry backoff, isolate connection establishment in a separate worker or process when possible, and apply CPU or container limits where appropriate.

5. On trusted servers you control, keep SCRAM iteration counts at ordinary values. This does not defend against an attacker-controlled server, but it avoids unnecessary client cost when talking to legitimate servers.

Integer wraparound in multiple PostgreSQL server features allows an unprivileged database user to cause the server to undersize an allocation and write out-of-bounds. This may execute arbitrary code as the operating system user running the database. In applications that pass gigabyte-scale user inputs to the relevant database functions, the application input provider may achieve a segmentation fault. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

Covert timing channel in comparison of MD5-hashed password in PostgreSQL authentication allows an attacker to recover user credentials sufficient to authenticate. This does not affect scram-sha-256 passwords, the default in all supported releases. However, current databases may have MD5-hashed passwords originating in upgrades from PostgreSQL 13 or earlier. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

Last updated 22 May 2026

Integer wraparound in multiple PostgreSQL server features allows an unprivileged database user to cause the server to undersize an allocation and write out-of-bounds. This may execute arbitrary code as the operating system user running the database. In applications that pass gigabyte-scale user inputs to the relevant database functions, the application input provider may achieve a segmentation fault. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

Covert timing channel in comparison of MD5-hashed password in PostgreSQL authentication allows an attacker to recover user credentials sufficient to authenticate. This does not affect scram-sha-256 passwords, the default in all supported releases. However, current databases may have MD5-hashed passwords originating in upgrades from PostgreSQL 13 or earlier. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

Use of inherently dangerous function PQfn(..., resultisint=0, ...) in PostgreSQL libpq loexport(), loread(), lolseek64(), and lotell64() functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response. Like gets(), PQfn(..., resultisint=0, ...) stores arbitrary-length, server-determined data into a buffer of unspecified size. Because both the \loexport command in psql and pgdump call loread(), the server superuser can overwrite pgdump or psql stack memory. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

PostgreSQL type confusion via "internal" arguments

Missing authorization in PostgreSQL logical decoding allows a non-superuser holding REPLICATION privilege to dlopen any file visible to the operating system account running the server, via the choice of logical decoding plugin. This in turn runs arbitrary code as that account. Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

Deployment of the VPS.org one-click Supabase template deploys a PostgreSQL instance that is published on all interfaces (0.0.0.0:5432) with a default database password set to "postgres". Because Docker installs its own iptables rules, this exposure bypasses a standard host UFW configuration.

The Versa Director uses PostgreSQL (Postgres) to store operational and configuration data. It is also needed for High Availability function of the Versa Director. The default configuration has a common password across all instances of Versa Director. By default, Versa Director configures Postgres to listen on all network interfaces. This combination allows an unauthenticated attacker to access and administer the database or read local filesystem contents to escalate privileges on the system.

Exploitation Status: Versa Networks is not aware of this exploitation in any production systems. A proof of concept exists in the lab environment.

Workarounds or Mitigation: Starting with the latest 22.1.4 version of Versa Director, the software will automatically restrict access to the Postgres and HA ports to only the local and peer Versa Directors. For older releases, Versa recommends performing manual hardening of HA ports. Please refer to the following link for the steps https://docs.versa-networks.com/Solutions/SystemHardening/PerformManualHardeningforVersaDirector#SecureHAPorts

This vulnerability is not exploitable on Versa Directors if published Firewall guidelines are implemented. We have validated that no Versa-hosted head ends have been affected by this vulnerability. All Versa-hosted head ends are patched and hardened.

Please contact Versa Technical Support or Versa account team for any further assistance.

Software Download Links: 22.1.4: https://support.versa-networks.com/support/solutions/articles/23000026708-release-22-1-4

Last updated 22 May 2026

Uncontrolled recursion in PostgreSQL SSL and GSS negotiation allows an attacker able to connect to a PostgreSQL AFUNIX socket to achieve sustained denial of service. If SSL and GSS are both disabled, an attacker can do the same via access to a PostgreSQL TCP socket. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

Impact

channelBinding=require connections can be silently downgraded from SCRAM-SHA-256-PLUS (with channel binding) to plain SCRAM-SHA-256 (without it), losing the man-in-the-middle protection the setting is meant to guarantee. An attacker who can intercept the TLS connection triggers the downgrade with a certificate whose signature algorithm has no tls-server-end-point channel-binding hash. Examples are Ed25519, Ed448, and post-quantum algorithms.

Two issues combine in releases 42.7.4 through 42.7.11:

1. The bundled com.ongres.scram:scram-client (3.1 or 3.2) returns an empty byte array instead of failing when it cannot derive the binding hash for such a certificate. This is the library issue tracked as GHSA-p9jg-fcr6-3mhf. 2. pgJDBC does not enforce channelBinding=require where it matters. ScramAuthenticator checks only that the server advertised a -PLUS mechanism; it neither rejects the empty binding nor checks that the negotiated mechanism uses channel binding. The connection therefore downgrades silently, and would do so even against a fixed scram-client, because the missing enforcement is in pgJDBC's own code.

Only connections that set channelBinding=require are affected. Under the default prefer policy, and under allow or disable, falling back to plain SCRAM is the documented behaviour. Releases before 42.7.4 are unaffected, because they do not support channel binding.

Patches

Fixed in pgJDBC 42.7.12. pgJDBC now enforces channel binding in its own code, independently of the scram-client version:

- Under channelBinding=require, it fails the connection when no channel-binding data can be extracted from the server certificate, instead of passing an empty value to the SCRAM client. The error names the certificate signature algorithm. - After negotiation, it requires the selected mechanism to use channel binding (a -PLUS mechanism) whenever channelBinding=require is set, regardless of how negotiation resolved.

Upgrade to 42.7.12 or later.

Workarounds

No pgJDBC setting restores channel-binding enforcement on an affected release; upgrading is the fix.

If you cannot upgrade immediately, verify the server certificate at the TLS layer so that a man-in-the-middle cannot present a substitute certificate. Set sslmode=verify-full with a truststore that contains only your server's CA. This defence is independent of channel binding and blocks the same attacker. Connections that rely on channelBinding=require in place of certificate verification have no equivalent workaround and should upgrade.

References

- GHSA-p9jg-fcr6-3mhf — the related com.ongres.scram:scram-client issue (root cause of the empty channel-binding value). - scram-client 3.3 release (library fix): https://github.com/ongres/scram/releases/tag/3.3 - pgJDBC fix in 42.7.12: commit

Incorrect ownership assignment in PostgreSQL ALTER TABLE ALTER TYPE command reassigns ownership of dependent statistics objects to the current user. This wrongly allows the table owner to run DROP STATISTICS and ALTER STATISTICS via this improper ownership. It wrongly denies those commands to the prior statistics object owner. DROP TABLE remains able to remove statistics objects, so this exploit achieves nothing in many ownership arrangements. Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

Missing authorization in PostgreSQL DDL commands allows an object creator to achieve denial of service against ALTER and DROP of the type, via creating a dependency on the type. Many DDL operations did check the privilege, but assigning a range subtype and referencing the type from an SQL expression did not. Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

Heap buffer overflow in PostgreSQL pgdump of long function transform lists allows an object creator to execute arbitrary code as the operating system user running pgdump, via a crafted transform list. Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

PostgreSQL psql COPY FROM STDIN early failure processes data lines as psql commands

Buffer over-read in PostgreSQL ascii() SQL function allows a user to disclose up to 3 bytes after the end of a specific allocation, via a crafted text value. This is the same class of defect that CVE-2026-2006 fixed, though this instance has less impact. Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

PostgreSQL psql \unrestrict lets superuser of pgdump origin server execute arbitrary code in psql client

PostgreSQL type confusion in cursor CLOSE + DECLARE executes arbitrary code

Integer underflow in PostgreSQL ECPG allows a database server administrator to achieve temporary denial of service against the ECPG client via sending a bytea value lacking the mandatory prefix. The client overwrites a huge memory region with bytes outside attacker knowledge or control. This typically yields a simple SIGSEGV, but rare cases might achieve client-specific integrity impact via the write. Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

Type confusion in PostgreSQL pgrestoreattributestats() allows an object creator to execute arbitrary code as the operating system user running the database, via conflation of range and multirange values. Within major version 18, minor versions before PostgreSQL 18.6 are affected. Versions before PostgreSQL 18 are unaffected.

Integer wraparound in PostgreSQL fuzzystrmatch allows a user to direct writes to a huge range of addresses, executing arbitrary code as the operating system user running the database, via extreme inputs to SQL function levenshtein() or levenshteinlessequal(). Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

PostgreSQL expression deparse allows SQL injection via EXTRACT argument

Improper enforcement of message integrity in PostgreSQL GSSAPI support allows a user to negotiate GSSAPI contrary to pghba.conf rules, via initial direct TLS connection. Despite a pghba.conf that appears to require GSSAPI, the connection may exchange data over TLS encryption alone. If the TLS settings are more permissive than the GSS settings, the connection may continue with lesser protection. Within major versions 17-18, minor versions before PostgreSQL 18.6 and 17.11 are affected. Versions before PostgreSQL 17 are unaffected.

Stack buffer overflow in PostgreSQL argument name matching allows an object creator to achieve unknown impacts via OUT parameter count. The attack can write only 0x0 and 0x1 bytes. Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

Buffer over-read in PostgreSQL pgtrgm index picksplit function reads past end of a heap buffer. This might allow a table maintainer to infer limited memory values, via the lossy signal of index split choices. Versions before PostgreSQL 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.