RHSA-2026:70698
Vulnerability from csaf_redhat - Published: 2026-09-23 10:57 - Updated: 2026-09-24 17:29A flaw was found in PgBouncer. An unauthenticated remote attacker can exploit an integer overflow in the packet buffer growth logic by providing sufficiently large input. This causes the buffer size computation to overflow, leading to an infinite loop. As a result, a CPU core is saturated, and all pooled connections are stalled, causing a Denial of Service.
| Product | Identifier | Version | Remediation |
|---|---|---|---|
| Unresolved product id: Red Hat Hardened Images:pgbouncer-0:1.26.0-0.1.hum1@aarch64 | — |
Vendor Fix
fix
Workaround
|
|
| Unresolved product id: Red Hat Hardened Images:pgbouncer-0:1.26.0-0.1.hum1@src | — |
Vendor Fix
fix
Workaround
|
|
| Unresolved product id: Red Hat Hardened Images:pgbouncer-0:1.26.0-0.1.hum1@x86_64 | — |
Vendor Fix
fix
Workaround
|
A flaw was found in PgBouncer. A malicious or compromised PostgreSQL backend can exploit a missing upper bound on the key derivation iteration count during SCRAM (Salted Challenge Response Authentication Mechanism) authentication. This can lead to uncontrolled CPU consumption in PgBouncer, effectively stopping it from serving traffic for all other databases and clients it manages. This results in a Denial of Service (DoS) for all connected services.
A flaw was found in PgBouncer. Missing validation of a mandatory attribute in the SCRAM client-final-message parser allows an unauthenticated remote attacker to crash the process. By sending a malformed message, the parser can report success while a required value remains unset, leading to a NULL pointer dereference. This crash occurs before any credentials are verified and terminates all pooled connections, resulting in a Denial of Service.
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},
"products": [
"Red Hat Hardened Images:pgbouncer-0:1.26.0-0.1.hum1@aarch64",
"Red Hat Hardened Images:pgbouncer-0:1.26.0-0.1.hum1@src",
"Red Hat Hardened Images:pgbouncer-0:1.26.0-0.1.hum1@x86_64"
]
}
],
"threats": [
{
"category": "impact",
"details": "Important"
}
],
"title": "pgbouncer: PgBouncer: Denial of Service via malformed SCRAM client-final-message"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.