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Buffer overflows in BSD-based FTP servers allows remote attackers to execute arbitrary commands via a long pattern string containing a {} sequence, as seen in (1) gopendir, (2) glstat, (3) gstat, and (4) the glob0 buffer as used in the glob functions glob2 and glob3.
Buffer overflow in IPSEC authentication mechanism for OpenBSD 2.8 and earlier allows remote attackers to cause a denial of service and possibly execute arbitrary commands via a malformed Authentication header (AH) IPv4 option.
Buffer overflow in BSD-based telnetd telnet daemon on various operating systems allows remote attackers to execute arbitrary commands via a set of options including AYT (Are You There), which is not properly handled by the telrcv function.
CORE SDI SSH1 CRC-32 compensation attack detector allows remote attackers to execute arbitrary commands on an SSH server or client via an integer overflow.
One-byte buffer overflow in replydirname function in BSD-based ftpd allows remote attackers to gain root privileges.
Format string vulnerabilities in OpenBSD ssh program (and possibly other BSD-based operating systems) allow attackers to gain root privileges.
Format string vulnerability in talkd in OpenBSD and possibly other BSD-based OSes allows remote attackers to execute arbitrary commands via a user name that contains format characters.
OpenSSH does not properly drop privileges when the UseLogin option is enabled, which allows local users to execute arbitrary commands by providing the command to the ssh daemon.
Buffer overflow in bootpd on OpenBSD, FreeBSD, and Linux systems via a malformed header type.
FreeBSD mmap function allows users to modify append-only or immutable files.
A "buffer management error" in bufferappendspace of buffer.c for OpenSSH before 3.7 may allow remote attackers to execute arbitrary code by causing an incorrect amount of memory to be freed and corrupting the heap, a different vulnerability than CVE-2003-0695.
The SSH1 PAM challenge response authentication in OpenSSH 3.7.1 and 3.7.1p1, when Privilege Separation is disabled, does not check the result of the authentication attempt, which can allow remote attackers to gain privileges.
Integer overflow in sshd in OpenSSH 2.9.9 through 3.3 allows remote attackers to execute arbitrary code during challenge response authentication (ChallengeResponseAuthentication) when OpenSSH is using SKEY or BSDAUTH authentication.
Buffer overflow in sshd in OpenSSH 2.3.1 through 3.3 may allow remote attackers to execute arbitrary code via a large number of responses during challenge response authentication when OpenBSD is using PAM modules with interactive keyboard authentication (PAMAuthenticationViaKbdInt).
Off-by-one error in the channel code of OpenSSH 2.0 through 3.0.2 allows local users or remote malicious servers to gain privileges.
Buffer overflow in the ReadFontAlias function in XFree86 4.1.0 to 4.3.0, when using the CopyISOLatin1Lowered function, allows local or remote authenticated users to execute arbitrary code via a malformed entry in the font alias (font.alias) file, a different vulnerability than CVE-2004-0083 and CVE-2004-0106.
Flaw bug created to hold information about an old flaw we knew something about. For more details see the MITRE CVE description.
Buffer overflow in the sppp driver in FreeBSD 4.11 through 6.1, NetBSD 2.0 through 4.0 beta before 20060823, and OpenBSD 3.8 and 3.9 before 20060902 allows remote attackers to cause a denial of service (panic), obtain sensitive information, and possibly execute arbitrary code via crafted Link Control Protocol (LCP) packets with an option length that exceeds the overall length, which triggers the overflow in (1) pppoe and (2) ippp. NOTE: this issue was originally incorrectly reported for the ppp driver.
Heap-based buffer overflow in proxyutil.c for modproxy in Apache 1.3.25 to 1.3.31 allows remote attackers to cause a denial of service (process crash) and possibly execute arbitrary code via a negative Content-Length HTTP header field, which causes a large amount of data to be copied.
isakmpd in OpenBSD 3.4 and earlier allows remote attackers to cause a denial of service via an ISAKMP packet with a malformed Cert Request payload, which causes an integer underflow that is used in a malloc operation that is not properly handled, as demonstrated by the Striker ISAKMP Protocol Test Suite.
Buffer overflow in ReadFontAlias from dirfile.c of XFree86 4.1.0 through 4.3.0 allows local users and remote attackers to execute arbitrary code via a font alias file (font.alias) with a long token, a different vulnerability than CVE-2004-0084 and CVE-2004-0106.
Double free vulnerability for the errorprogname string in CVS 1.12.x through 1.12.8, and 1.11.x through 1.11.16, may allow remote attackers to execute arbitrary code.
CVS 1.12.x through 1.12.8, and 1.11.x through 1.11.16, does not properly handle malformed "Entry" lines, which prevents a NULL terminator from being used and may lead to a denial of service (crash), modification of critical program data, or arbitrary code execution.
servenotify in CVS 1.12.x through 1.12.8, and 1.11.x through 1.11.16, does not properly handle empty data lines, which may allow remote attackers to perform an "out-of-bounds" write for a single byte to execute arbitrary code or modify critical program data.
Buffer overflow in kern/uipcmbuf2.c in OpenBSD 3.9 and 4.0 allows remote attackers to execute arbitrary code via fragmented IPv6 packets due to "incorrect mbuf handling for ICMP6 packets." NOTE: this was originally reported as a denial of service.
NFS in a BSD derived codebase, as used in OpenBSD through 7.4 and FreeBSD through 14.0-RELEASE, allows remote attackers to execute arbitrary code via a bug that is unrelated to memory corruption.
In OpenBSD 7.5 before errata 008 and OpenBSD 7.4 before errata 021, avoid possible mbuf double free in NFS client and server implementation, do not use uninitialized variable in error handling of NFS server.
Off-by-one error in the fbrealpath() function, as derived from the realpath function in BSD, may allow attackers to execute arbitrary code, as demonstrated in wu-ftpd 2.5.0 through 2.6.2 via commands that cause pathnames of length MAXPATHLEN+1 to trigger a buffer overflow, including (1) STOR, (2) RETR, (3) APPE, (4) DELE, (5) MKD, (6) RMD, (7) STOU, or (8) RNTO.
Last updated 25 August 2025
libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/authsubr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).