PostgreSQL <18.4 OOB Integer Wraparound Undersize Allocation
CVE-2026-6473 Published on May 14, 2026
PostgreSQL server undersizes allocations, via integer wraparound
Integer wraparound in multiple PostgreSQL server features allows an unprivileged database user to cause the server to undersize an allocation and write out-of-bounds. This may execute arbitrary code as the operating system user running the database. In applications that pass gigabyte-scale user inputs to the relevant database functions, the application input provider may achieve a segmentation fault. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.
Vulnerability Analysis
CVE-2026-6473 can be exploited with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.
Weakness Type
Integer Overflow or Wraparound
The software performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. An integer overflow or wraparound occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may wrap to become a very small or negative number. While this may be intended behavior in circumstances that rely on wrapping, it can have security consequences if the wrap is unexpected. This is especially the case if the integer overflow can be triggered using user-supplied inputs. This becomes security-critical when the result is used to control looping, make a security decision, or determine the offset or size in behaviors such as memory allocation, copying, concatenation, etc.
Products Associated with CVE-2026-6473
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Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.