CVE-2026-0708
Description
A flaw was found in libucl. A remote attacker could exploit this by providing a specially crafted Universal Configuration Language (UCL) input that contains a key with an embedded null byte. This can cause a segmentation fault (SEGV fault) in the ucl_object_emit function when parsing and emitting the object, leading to a Denial of Service (DoS) for the affected system.
Statement
This vulnerability is rated Important for Red Hat products. A flaw in the libucl library allows a remote attacker to trigger a Denial of Service (DoS) by providing specially crafted Universal Configuration Language (UCL) input containing an embedded null byte. This can lead to a segmentation fault when the malformed input is processed.
Mitigation
To mitigate this issue, applications utilizing `libucl` should avoid processing untrusted input that contains keys with embedded null bytes, especially when operating in `UCL_PARSER_ZEROCOPY` mode. Restricting input to trusted sources can reduce exposure.
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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