CWE-124Base

Buffer Underwrite ('Buffer Underflow')

Incomplete in the CWE catalog · 39 CVEs mapped

39
CVEs mapped
6.5
Median CVSS
What it is

The product writes to a buffer using an index or pointer that references a memory location prior to the beginning of the buffer.

Recent examples
4.3cvss
CVE-2026-40013

CVE-2026-40013 - MEDIUM Severity Vulnerability

An attacker that has valid credentials can submit a Sieve script containing an extreme numeric literal, which causes an out-of-bounds write when the ManageSieve service compiles the script. This causes memory corruption and an observed crash of the ManageSieve process, resulting in denial of service for script management. This might be able to be used for remote code execution. Disable the ManageSieve service if users do not need remote Sieve script management. Update to non-vulnerable version. No publicly available exploits are known.

MEDIUMno explanation yet
0%
epss
none
CVE-2026-73075

CVE-2026-73075 - UNKNOWN Severity Vulnerability

Vim is an open source, command line text editor. From 9.2.0469 until 9.2.0843, popup_mark_opacity_zindex() in src/popupwin.c can use a negative w_winrow for a text-property-anchored popup with clipwindow and opacity, indexing before the screen array instead of accounting for w_popup_topoff and causing an out-of-bounds read and conditional write. This issue is fixed in version 9.2.0843.

no explanation yet
0%
epss
6.7cvss
CVE-2026-71969

CVE-2026-71969 - MEDIUM Severity Vulnerability

OP-TEE OS through 4.10.0, fixed in commit 7b8b494, contains a buffer underwrite vulnerability in the RSA NOPAD encrypt and decrypt operations within the mbedTLS software backend and SE050 hardware driver that allows a malicious Trusted Application to corrupt secure-world heap memory by supplying an input length exceeding the RSA modulus size. When src_len exceeds rsa_len, the subtraction expression wraps to a large unsigned value, causing a subsequent memcpy to write attacker-controlled data before the destination buffer in S-EL1 secure-world heap memory.

MEDIUMno explanation yet
0%
epss
The record
Technical detail
CWE ID
CWE-124
Abstraction
Base
Structure
Simple
Status
Incomplete
References (2)