CVE-2026-14677·PostgreSQL vulnerability

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at 0.42% — higher than 35% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2026-14677 scores 8.8 on CVSS, so a successful attack would be serious — but at 0.42%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

How to fix this CVE

Upgrade PostgreSQL to version 18.6 or later to remediate an integer wraparound vulnerability affecting 32-bit builds of pltcl and plperl extensions. This flaw allows database object creators to trigger undersized memory allocations leading to out-of-bounds writes and potential arbitrary code execution. Organizations running PostgreSQL 18.0–18.5 should prioritize this update to prevent privilege escalation within the database context.

sudo dnf upgrade postgresql-server postgresql-contrib

How to check if you are affected

1. Step 1: Check installed PostgreSQL version with: psql --version or sudo -u postgres psql -c 'SELECT version();'
2. Step 2: Verify if pltcl or plperl extensions are installed by querying: SELECT * FROM pg_available_extensions WHERE name IN ('pltcl', 'plperl');
3. Step 3: Review PostgreSQL server logs for unusual memory allocation errors or segmentation faults around user-defined function creation: sudo tail -100 /var/log/postgresql/postgresql.log | grep -i 'wraparound\|allocation\|segfault'
4. Step 4: After patching, confirm the version with psql --version and verify no extension re-initialization was needed: sudo -u postgres psql -c 'SELECT extname, extversion FROM pg_extension WHERE extname IN ("pltcl", "plperl");'

FAQ

Related PostgreSQL CVEs

References

• https://www.postgresql.org/support/security/CVE-2026-14677/