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.

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.

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.

The TCP stack in 4.3BSD Net/2, as used in FreeBSD 5.4, NetBSD possibly 2.0, and OpenBSD possibly 3.6, does not properly implement the session timer, which allows remote attackers to cause a denial of service (resource consumption) via crafted packets.

The glob implementation in libc in FreeBSD 7.3 and 8.1, NetBSD 5.0.2, and OpenBSD 4.7, and Libsystem in Apple Mac OS X before 10.6.8, allows remote authenticated users to cause a denial of service (CPU and memory consumption) via crafted glob expressions that do not match any pathnames, as demonstrated by glob expressions in STAT commands to an FTP daemon, a different vulnerability than CVE-2010-2632.

openssh: remote DoS in sftp via crafted glob expressions

The (1) remote_glob function in sftp-glob.c and the (2) process_put function in sftp.c in OpenSSH 5.8 and earlier, as used in FreeBSD 7.3 and 8.1, NetBSD 5.0.2, OpenBSD 4.7, and other products, allow remote authenticated users to cause a denial of service (CPU and memory consumption) via crafted glob expressions that do not match any pathnames, as demonstrated by glob expressions in SSH_FXP_STAT requests to an sftp daemon, a different vulnerability than CVE-2010-2632.

BSD compress LZW decoder buffer overflow

The LZW decompressor in (1) the BufCompressedFill function in fontfile/decompress.c in X.Org libXfont before 1.4.4 and (2) compress/compress.c in 4.3BSD, as used in zopen.c in OpenBSD before 3.8, FreeBSD, NetBSD 4.0.x and 5.0.x before 5.0.3 and 5.1.x before 5.1.1, FreeType 2.1.9, and other products, does not properly handle code words that are absent from the decompression table when encountered, which allows context-dependent attackers to trigger an infinite loop or a heap-based buffer overflow, and possibly execute arbitrary code, via a crafted compressed stream, a related issue to CVE-2006-1168 and CVE-2011-2896.

apr: unconstrained recursion in apr_fnmatch

Stack consumption vulnerability in the fnmatch implementation in apr_fnmatch.c in the Apache Portable Runtime (APR) library before 1.4.3 and the Apache HTTP Server before 2.2.18, and in fnmatch.c in libc in NetBSD 5.1, OpenBSD 4.8, FreeBSD, Apple Mac OS X 10.6, Oracle Solaris 10, and Android, allows context-dependent attackers to cause a denial of service (CPU and memory consumption) via *? sequences in the first argument, as demonstrated by attacks against mod_autoindex in httpd.

kernel: drm_modeset_ctl signedness issue

Integer signedness error in the drm_modeset_ctl function in (1) drivers/gpu/drm/drm_irq.c in the Direct Rendering Manager (DRM) subsystem in the Linux kernel before 2.6.38 and (2) sys/dev/pci/drm/drm_irq.c in the kernel in OpenBSD before 4.9 allows local users to trigger out-of-bounds write operations, and consequently cause a denial of service (system crash) or possibly have unspecified other impact, via a crafted num_crtcs (aka vb_num) structure member in an ioctl argument.

Multiple integer overflows in the glob implementation in libc in OpenBSD before 4.9 might allow context-dependent attackers to have an unspecified impact via a crafted string, related to the GLOB_APPEND and GLOB_DOOFFS flags, a different issue than CVE-2011-0418.

In OpenBSD 7.2, a TCP packet with destination port 0 that matches a pf divert-to rule can crash the kernel.

An issue was discovered in x509/x509_verify.c in LibreSSL before 3.6.1, and in OpenBSD before 7.2 errata 001. x509_verify_ctx_add_chain does not store errors that occur during leaf certificate verification, and therefore an incorrect error is returned. This behavior occurs when there is an installed verification callback that instructs the verifier to continue upon detecting an invalid certificate.

x509/x509_verify.c in LibreSSL before 3.4.2, and OpenBSD before 7.0 errata 006, allows authentication bypass because an error for an unverified certificate chain is sometimes discarded.

A double free or use after free could occur after SSL_clear in OpenBSD 7.2 before errata 026 and 7.3 before errata 004, and in LibreSSL before 3.6.3 and 3.7.x before 3.7.3. NOTE: OpenSSL is not affected.

OpenBSD 7.3 before errata 014 is missing an argument-count bounds check in console terminal emulation. This could cause incorrect memory access and a kernel crash after receiving crafted DCS or CSI terminal escape sequences.

In OpenBGPD before 8.1, incorrect handling of BGP update data (length of path attributes) set by a potentially distant remote actor may cause the system to incorrectly reset a session. This is fixed in OpenBSD 7.3 errata 006.

slaacd in OpenBSD 6.9 and 7.0 before 2022-03-22 has an integer signedness error and resultant heap-based buffer overflow triggerable by a crafted IPv6 router advertisement. NOTE: privilege separation and pledge can prevent exploitation.

engine.c in slaacd in OpenBSD 6.9 and 7.0 before 2022-02-21 has a buffer overflow triggerable by an IPv6 router advertisement with more than seven nameservers. NOTE: privilege separation and pledge can prevent exploitation.

kernel: processing fragmented frames as full frames

An issue was discovered in the kernel in OpenBSD 6.6. The WEP, WPA, WPA2, and WPA3 implementations treat fragmented frames as full frames. An adversary can abuse this to inject arbitrary network packets, independent of the network configuration.

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.