CVE-2026-6637 (GCVE-0-2026-6637)
Vulnerability from cvelistv5 – Published: 2026-05-14 13:00 – Updated: 2026-05-15 03:56
VLAI
EPSS
VEX
Title
PostgreSQL refint allows stack buffer overflow and SQL injection
Summary
Stack buffer overflow in PostgreSQL module "refint" allows an unprivileged database user to execute arbitrary code as the operating system user running the database. A distinct attack is possible if the application declares a user-controlled column as a "refint" cascade primary key and facilitates user-controlled updates to that column. In that case, a SQL injection allows a primary key update value provider to execute arbitrary SQL as the database user performing the primary key update. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.
Severity
8.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-14 00:00 UTC
CWE
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| n/a | PostgreSQL |
Affected:
18 , < 18.4
(rpm)
Affected: 17 , < 17.10 (rpm) Affected: 16 , < 16.14 (rpm) Affected: 15 , < 15.18 (rpm) Affected: 0 , < 14.23 (rpm) |
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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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.
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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.