iked in OpenIKED, as used in OpenBSD through 6.7, allows authentication bypass because ca.c has the wrong logic for checking whether a public key matches.

openbsd

An issue has been found in PowerDNS Recursor 4.1.0 up to and including 4.3.0. It allows an attacker (with enough privileges to change the system's hostname) to cause disclosure of uninitialized memory content via a stack-based out-of-bounds read. It only occurs on systems where gethostname() does not have '\0' termination of the returned string if the hostname is larger than the supplied buffer. (Linux systems are not affected because the buffer is always large enough. OpenBSD systems are not affected because the returned hostname always has '\0' termination.) Under some conditions, this issue can lead to the writing of one '\0' byte out-of-bounds on the stack, causing a denial of service or possibly arbitrary code execution.

powerdns

smtp_mailaddr in smtp_session.c in OpenSMTPD 6.6, as used in OpenBSD 6.6 and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session, as demonstrated by shell metacharacters in a MAIL FROM field. This affects the "uncommented" default configuration. The issue exists because of an incorrect return value upon failure of input validation.

openbsd · debian · fedoraproject · canonical

OpenBSD through 6.6 allows local users to escalate to root because a check for LD_LIBRARY_PATH in setuid programs can be defeated by setting a very small RLIMIT_DATA resource limit. When executing chpass or passwd (which are setuid root), _dl_setup_env in ld.so tries to strip LD_LIBRARY_PATH from the environment, but fails when it cannot allocate memory. Thus, the attacker is able to execute their own library code as root.

openbsd

A vulnerability was discovered in Linux, FreeBSD, OpenBSD, MacOS, iOS, and Android that allows a malicious access point, or an adjacent user, to determine if a connected user is using a VPN, make positive inferences about the websites they are visiting, and determine the correct sequence and acknowledgement numbers in use, allowing the bad actor to inject data into the TCP stream. This provides everything that is needed for an attacker to hijack active connections inside the VPN tunnel.

freebsd · linux · openbsd · apple

lib/libc/stdlib/random.c in OpenBSD returns 0 when seeded with 0.

dietlibc_project · openbsd · debian

OpenBSD 6.6, in a non-default configuration where S/Key or YubiKey authentication is enabled, allows local users to become root by leveraging membership in the auth group. This occurs because root's file can be written to /etc/skey or /var/db/yubikey, and need not be owned by root.

openbsd

libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/auth_subr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).

openbsd

xlock in OpenBSD 6.6 allows local users to gain the privileges of the auth group by providing a LIBGL_DRIVERS_PATH environment variable, because xenocara/lib/mesa/src/loader/loader.c mishandles dlopen.

openbsd

In OpenBSD 6.6, local users can use the su -L option to achieve any login class (often excluding root) because there is a logic error in the main function in su/su.c.

openbsd

An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD. A setusercontext(3) call with flags to change the UID, primary GID, and secondary GIDs was replaced (on certain platforms: Linux and possibly NetBSD) with a single setuid(2) call. This resulted in neither changing the group id nor initializing secondary group ids.

doas_project · linux

An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD. On platforms without strtonum(3), sscanf was used without checking for error cases. Instead, the uninitialized variable errstr was checked and in some cases returned success even if sscanf failed. The result was that, instead of reporting that the supplied username or group name did not exist, it would execute the command as root.

doas_project

OpenBSD kernel version <= 6.5 can be forced to create long chains of TCP SACK holes that causes very expensive calls to tcp_sack_option() for every incoming SACK packet which can lead to a denial of service.

openbsd

The barracudavpn component of the Barracuda VPN Client prior to version 5.0.2.7 for Linux, macOS, and OpenBSD runs as a privileged process and can allow an unprivileged local attacker to load a malicious library, resulting in arbitrary code executing as root.

barracuda · apple · linux · openbsd

tss_alloc in sys/arch/i386/i386/gdt.c in OpenBSD 6.2 and 6.3 has a Local Denial of Service (system crash) due to incorrect I/O port access control on the i386 architecture.

openbsd

elf.c in the Binary File Descriptor (BFD) library (aka libbfd), as distributed in GNU Binutils 2.29.1, does not validate sizes of core notes, which allows remote attackers to cause a denial of service (bfd_getl32 heap-based buffer over-read and application crash) via a crafted object file, related to elfcore_grok_netbsd_procinfo, elfcore_grok_openbsd_procinfo, and elfcore_grok_nto_status.

gnu

The OpenBSD qsort() function is recursive, and not randomized, an attacker can construct a pathological input array of N elements that causes qsort() to deterministically recurse N/4 times. This allows attackers to consume arbitrary amounts of stack memory and manipulate stack memory to assist in arbitrary code execution attacks. This affects OpenBSD 6.1 and possibly earlier versions.

openbsd

A flaw exists in OpenBSD's implementation of the stack guard page that allows attackers to bypass it resulting in arbitrary code execution using setuid binaries such as /usr/bin/at. This affects OpenBSD 6.1 and possibly earlier versions.

openbsd

httpd in OpenBSD allows remote attackers to cause a denial of service (memory consumption) via a series of requests for a large file using an HTTP Range header.

openbsd

Integer overflow in the uvm_map_isavail function in uvm/uvm_map.c in OpenBSD 5.9 allows local users to cause a denial of service (kernel panic) via a crafted mmap call, which triggers the new mapping to overlap with an existing mapping.

openbsd

OpenBSD 5.8 and 5.9 allows local users to cause a denial of service (NULL pointer dereference and panic) via a sysctl call with a path starting with 10,9.

openbsd