GNU » Glibc : Security Vulnerabilities, CVEs, (Overflow)

sprintf in the GNU C Library (glibc) 2.37 has a buffer overflow (out-of-bounds write) in some situations with a correct buffer size. This is unrelated to CWE-676. It may write beyond the bounds of the destination buffer when attempting to write a padded, thousands-separated string representation of a number, if the buffer is allocated the exact size required to represent that number as a string. For example, 1,234,567 (with padding to 13) overflows by two bytes.

An integer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a very long message, leading to an incorrect calculation of the buffer size to store the message, resulting in undefined behavior. This issue affects glibc 2.37 and newer.

An off-by-one heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a message bigger than INT_MAX bytes, leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.

A heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when the openlog function was not called, or called with the ident argument set to NULL, and the program name (the basename of argv[0]) is bigger than 1024 bytes, resulting in an application crash or local privilege escalation. This issue affects glibc 2.36 and newer.

A buffer overflow was discovered in the GNU C Library's dynamic loader ld.so while processing the GLIBC_TUNABLES environment variable. This issue could allow a local attacker to use maliciously crafted GLIBC_TUNABLES environment variables when launching binaries with SUID permission to execute code with elevated privileges.

A vulnerability was found in GNU C Library 2.38. It has been declared as critical. This vulnerability affects the function __monstartup of the file gmon.c of the component Call Graph Monitor. The manipulation leads to buffer overflow. It is recommended to apply a patch to fix this issue. VDB-220246 is the identifier assigned to this vulnerability. NOTE: The real existence of this vulnerability is still doubted at the moment. The inputs that induce this vulnerability are basically addresses of the running application that is built with gmon enabled. It's basically trusted input or input that needs an actual security flaw to be compromised or controlled.

The deprecated compatibility function clnt_create in the sunrpc module of the GNU C Library (aka glibc) through 2.34 copies its hostname argument on the stack without validating its length, which may result in a buffer overflow, potentially resulting in a denial of service or (if an application is not built with a stack protector enabled) arbitrary code execution.

The deprecated compatibility function svcunix_create in the sunrpc module of the GNU C Library (aka glibc) through 2.34 copies its path argument on the stack without validating its length, which may result in a buffer overflow, potentially resulting in a denial of service or (if an application is not built with a stack protector enabled) arbitrary code execution.

The wordexp function in the GNU C Library (aka glibc) through 2.33 may crash or read arbitrary memory in parse_param (in posix/wordexp.c) when called with an untrusted, crafted pattern, potentially resulting in a denial of service or disclosure of information. This occurs because atoi was used but strtoul should have been used to ensure correct calculations.

A flaw was found in glibc. An off-by-one buffer overflow and underflow in getcwd() may lead to memory corruption when the size of the buffer is exactly 1. A local attacker who can control the input buffer and size passed to getcwd() in a setuid program could use this flaw to potentially execute arbitrary code and escalate their privileges on the system.

sysdeps/i386/ldbl2mpn.c in the GNU C Library (aka glibc or libc6) before 2.23 on x86 targets has a stack-based buffer overflow if the input to any of the printf family of functions is an 80-bit long double with a non-canonical bit pattern, as seen when passing a \x00\x04\x00\x00\x00\x00\x00\x00\x00\x04 value to sprintf. NOTE: the issue does not affect glibc by default in 2016 or later (i.e., 2.23 or later) because of commits made in 2015 for inlining of C99 math functions through use of GCC built-ins. In other words, the reference to 2.23 is intentional despite the mention of "Fixed for glibc 2.33" in the 26649 reference.

GNU Libc current is affected by: Mitigation bypass. The impact is: Attacker may bypass stack guard protection. The component is: nptl. The attack vector is: Exploit stack buffer overflow vulnerability and use this bypass vulnerability to bypass stack guard. NOTE: Upstream comments indicate "this is being treated as a non-security bug and no real threat.

An AVX-512-optimized implementation of the mempcpy function in the GNU C Library (aka glibc or libc6) 2.27 and earlier may write data beyond the target buffer, leading to a buffer overflow in __mempcpy_avx512_no_vzeroupper.

stdlib/canonicalize.c in the GNU C Library (aka glibc or libc6) 2.27 and earlier, when processing very long pathname arguments to the realpath function, could encounter an integer overflow on 32-bit architectures, leading to a stack-based buffer overflow and, potentially, arbitrary code execution.

The malloc implementation in the GNU C Library (aka glibc or libc6), from version 2.24 to 2.26 on powerpc, and only in version 2.26 on i386, did not properly handle malloc calls with arguments close to SIZE_MAX and could return a pointer to a heap region that is smaller than requested, eventually leading to heap corruption.

An integer overflow in the implementation of the posix_memalign in memalign functions in the GNU C Library (aka glibc or libc6) 2.26 and earlier could cause these functions to return a pointer to a heap area that is too small, potentially leading to heap corruption.

A buffer overflow in glibc 2.5 (released on September 29, 2006) and can be triggered through the LD_LIBRARY_PATH environment variable. Please note that many versions of glibc are not vulnerable to this issue if patched for CVE-2017-1000366.

glibc contains a vulnerability that allows specially crafted LD_LIBRARY_PATH values to manipulate the heap/stack, causing them to alias, potentially resulting in arbitrary code execution. Please note that additional hardening changes have been made to glibc to prevent manipulation of stack and heap memory but these issues are not directly exploitable, as such they have not been given a CVE. This affects glibc 2.25 and earlier.

An SSE2-optimized memmove implementation for i386 in sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S in the GNU C Library (aka glibc or libc6) 2.21 through 2.27 does not correctly perform the overlapping memory check if the source memory range spans the middle of the address space, resulting in corrupt data being produced by the copy operation. This may disclose information to context-dependent attackers, or result in a denial of service, or, possibly, code execution.

The malloc function in the GNU C Library (aka glibc or libc6) 2.26 could return a memory block that is too small if an attempt is made to allocate an object whose size is close to SIZE_MAX, potentially leading to a subsequent heap overflow. This occurs because the per-thread cache (aka tcache) feature enables a code path that lacks an integer overflow check.

The glob function in glob.c in the GNU C Library (aka glibc or libc6) before 2.27 contains a buffer overflow during unescaping of user names with the ~ operator.

The GNU C Library (aka glibc or libc6) before 2.27 contains an off-by-one error leading to a heap-based buffer overflow in the glob function in glob.c, related to the processing of home directories using the ~ operator followed by a long string.

Stack-based buffer overflow in the clntudp_call function in sunrpc/clnt_udp.c in the GNU C Library (aka glibc or libc6) allows remote servers to cause a denial of service (crash) or possibly unspecified other impact via a flood of crafted ICMP and UDP packets.

Stack-based buffer overflow in the getaddrinfo function in sysdeps/posix/getaddrinfo.c in the GNU C Library (aka glibc or libc6) allows remote attackers to cause a denial of service (crash) via vectors involving hostent conversion. NOTE: this vulnerability exists because of an incomplete fix for CVE-2013-4458.

Stack-based buffer overflow in the nss_dns implementation of the getnetbyname function in GNU C Library (aka glibc) before 2.24 allows context-dependent attackers to cause a denial of service (stack consumption and application crash) via a long name.