CVE-2026-15742: PostgreSQL fuzzystrmatch writes effectively-arbitrary addresses, via integer wraparound

highCVSS 8.8CVE-2026-15742

CSIRTS triage

vendor: PostgreSQL product: PostgreSQL Memory corruption Remote code execution

What: The fuzzystrmatch extension writes to arbitrary memory addresses via integer wraparound.
Who is affected: PostgreSQL deployments with fuzzystrmatch extension enabled.
Urgency: High severity (CVSS 8.8); enables arbitrary code execution through memory corruption.
Action: Update PostgreSQL or disable fuzzystrmatch extension if not required.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 8.8
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-15742

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-157420.49% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 40% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-15742	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

high[NEW] [high] PostgreSQL: Multiple vulnerabilitiescert-bund
unknownUSN-8653-1: PostgreSQL vulnerabilitiesubuntu
unknownMultiple vulnerabilities in PostgreSQL (August 14, 2026)cert-fr-avis
highCVE-2026-15742: Integer wraparound in PostgreSQL fuzzystrmatch allows a user to direct writes to a huge range …nvd

Recent advisories for PostgreSQL fuzzystrmatch writes

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-15742: Integer wraparound in PostgreSQL fuzzystrmatch allows a user to direct writes to a huge range …nvd · 2026-08-13