CVE-2026-121942
Description
A flaw was found in zbar. An attacker could exploit this vulnerability by enticing a user to process a specially crafted SQ code image. During decoding, unchecked coordinates near image boundaries trigger an out-of-bounds memory read. This flaw allows an attacker to crash the application, resulting in a Denial of Service (DoS), or potentially disclose sensitive memory data.
Statement
This vulnerability is rated as Moderate impact because successful exploitation requires user interaction to process an untrusted, specially crafted image file and primarily results in application termination or limited memory disclosure rather than arbitrary code execution. While the library is consumed by applications decoding matrix codes, it is not enabled as an exposed network service by default in Red Hat environments, restricting the blast radius to the local application handling the input. Consequently, privilege boundaries remain intact and impact is limited to temporary denial of service or potential leakage of heap contents.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
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