CVE-2026-73146
Description
A flaw was found in svxlink's svxreflector component. A reentrant client deletion triggered via a sendError() write-failure path leads to a use-after-free on the client object. A remote attacker can trigger this condition to crash the reflector server or potentially achieve arbitrary code execution.
Statement
svxlink is not shipped in any Red Hat Enterprise product. It is available in Fedora as a community-maintained package.
Mitigation
Update svxlink to version 26.05.1 or later.
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Memory
The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.
Confidentiality
Technical Impact: Read Memory
Read operations on freed memory can sometimes leak sensitive information instead of causing a crash
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.
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