CVE-2023-4806
MediumCVSS 5.9Exploitation Probability (EPSS)
Elevated risk70th percentile - higher than 70% of all known CVEs
Summary
A use-after-free flaw has been found in glibc's getaddrinfo function. In an extremely rare scenario where an NSS module implements only specific hooks and the query meets certain conditions, an application crash may occur.
Risk Assessment
The risk for the organization is a potential crash of applications performing DNS resolution under specific, rare configurations. This could lead to service disruptions.
Recommendation
It is recommended to update glibc to a patched version (e.g., 2.38 or later). As a workaround, avoid using AI_ALL and AI_V4MAPPED flags in getaddrinfo calls.
Original NVD description (English source)
A flaw has been identified in glibc. In an extremely rare situation, the getaddrinfo function may access memory that has been freed, resulting in an application crash. This issue is only exploitable when a NSS module implements only the _nss_*_gethostbyname2_r and _nss_*_getcanonname_r hooks without implementing the _nss_*_gethostbyname3_r hook. The resolved name should return a large number of IPv6 and IPv4, and the call to the getaddrinfo function should have the AF_INET6 address family with AI_CANONNAME, AI_ALL and AI_V4MAPPED as flags.