Cyber Resilience

CVE-2026-6477

Memory Safety in Postgresql ≤ 14.23

Memory Safety
Published
14 May 2026
Modified
06 August 2026
Patch / advisory
View advisory
CVSS Score v3.1 8.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0045 37th percentile
Risk Priority 64 floored blend · peak EPSS

Summary

CVE-2026-6477 is a high-severity Use of Inherently Dangerous Function (CWE-242) vulnerability in Postgresql Postgresql. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 37th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Use of inherently dangerous function PQfn(..., result_is_int=0, ...) in PostgreSQL libpq lo_export(), lo_read(), lo_lseek64(), and lo_tell64() functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response. Like gets(), PQfn(..., result_is_int=0, ...) stores arbitrary-length, server-determined data…

more

into a buffer of unspecified size. Because both the \lo_export command in psql and pg_dump call lo_read(), the server superuser can overwrite pg_dump or psql stack memory. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

CWE(s)
CWE-242CWE-120

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-2005Same product: Postgresql Postgresql
CVE-2026-2007Same product: Postgresql Postgresql
CVE-2026-2004Same product: Postgresql Postgresql
CVE-2026-2003Same product: Postgresql Postgresql
CVE-2026-6637Same product: Postgresql Postgresql
CVE-2026-2006Same product: Postgresql Postgresql
CVE-2026-6473Same product: Postgresql Postgresql
CVE-2026-6474Same product: Postgresql Postgresql
CVE-2024-4317Same product: Postgresql Postgresql
CVE-2026-6472Same product: Postgresql Postgresql

Affected Assets

postgresql
postgresql
≤ 14.23 · 15.0 — 15.18 · 16.0 — 16.14

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V5.2.1

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and code analysis can locate calls to known dangerous functions after they have been written.

SI-10 Information Input Validation good match

Input validation directly enforces size checks before buffer copies.

SA-15 Development Process, Standards, and Tools partial match

Documented development standards and tools can explicitly prohibit or replace inherently dangerous functions.

SA-3 System Development Life Cycle partial match

An SDLC that incorporates security can embed rules against unsafe functions in coding and review phases.

SA-8 Security and Privacy Engineering Principles partial match

Engineering principles can mandate avoidance of unsafe library functions during design and coding.

SI-16 Memory Protection partial match

Memory protection limits the impact of an overflow once it occurs.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prohibit or replace inherently dangerous functions via coding standards, reviews, and tooling.

ID.RA-01 partial match
prevents

Vulnerability identification processes such as code review or scanning detect classic buffer overflows before exploitation.

PR.PS-02 partial match
prevents

Routine patching replaces vulnerable code containing unchecked buffer copies with corrected versions.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.28 Secure coding mostly match
prevents

Secure coding directly requires bounds-checked memory operations, addressing the root cause of CWE-120.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can surface calls to unsafe functions but does not prevent their introduction.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC processes include code review and static analysis that can detect dangerous function usage.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify input-size validation and safe buffer handling to mitigate classic buffer overflows.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure system architecture and engineering principles promote defensive coding patterns that reduce the likelihood of unchecked buffer copies.

A.8.19 Installation of software on operational systems none match
none

Controlled software installation reduces exposure to unsafe third-party code containing dangerous functions.

References