Vulnerabilidades do Red Hat Red Hat Enterprise Linux 8

A malicious or compromised Flatpak repository can write attacker-controlled content to arbitrary locations on the host filesystem via extract_extra_data(). On system installs, the write happens as root. Two issues combine: `files/extra` is resolved via path operations that follow symlinks, and blob names from `xa.extra-data-sources` are not sanitized against `..` traversal.

A flaw was found in sudo. When sudoers rules use NOTBEFORE or NOTAFTER time-based access restrictions with timestamps that omit the trailing 'Z' timezone indicator, the time evaluation relies on the TZ environment variable inherited from the calling user. Because sudo is a setuid-root program, an unprivileged local user can set TZ to an extreme timezone offset to shift the authorization window by up to approximately 25 hours, causing expired rules to be treated as valid. This allows the user to execute commands outside the intended time window. Authentication is not bypassed; only the time-based authorization check is affected.

A code execution flaw was found in Emacs, affecting versions prior to 31.2. The Flymake mode using language backends other than Lisp would execute arbitrary code from the edited file while performing syntax checking. Viewing or editing untrusted files using Emacs could lead to arbitrary code execution with the privileges of the user running Emacs.

A flaw was found in rpcbind. This vulnerability allows a remote, unauthenticated attacker to cause a Denial of Service (DoS) by sending a large number of unique requests. The rpcbind service records previously unseen RPC (Remote Procedure Call) statistics in unbounded in-memory lists, leading to persistent memory growth and increased CPU usage. This can degrade or exhaust service availability.

A flaw was found in libstdc++. An integer overflow can occur when processing large inputs to the aligned operator new in the C++ library. This vulnerability could lead to an undersized memory allocation, potentially causing memory corruption or application instability.

A heap-based buffer overflow was found in the DHCPv6 and TFTP response builders of libslirp. When the host is configured with a small interface MTU, a guest-supplied DHCPv6 CLIENTID option or TFTP blksize option can overflow the reply buffer with attacker-controlled content and length, resulting in denial of service and potentially arbitrary code execution in the host process. The default interface MTU is not affected.

A flaw was found in pki-core. The v2 REST ACL filter selects a tie-breaking permission for colliding literal and wildcard ACL keys using lexicographic string comparison rather than specificity, causing a wildcard-mapped permission to override a more specific literal-mapped permission when both match. In the CA's profile-management REST API this allows a request to POST /v2/profiles/raw -- intended to require Administrator-level profiles.create permission -- to instead be authorized under the lower-privileged profiles.approve permission held by the default Certificate Manager Agents group. The highest threat from this vulnerability is to confidentiality and integrity of the certificate authority's issuance policy.

A flaw was found in Cockpit. An unauthenticated remote attacker can exploit this vulnerability by initiating and sustaining numerous simultaneous connections to the `cockpit-tls` service. This forces the service to create an unbounded number of detached threads, consuming system resources such as memory and file descriptors. The primary consequence is a denial of service (DoS), leading to degradation or complete unavailability of the Cockpit service for legitimate users.

A flaw was found in QEMU. The VAPIC setup hypercall in hw/i386/vapic.c does not validate that the writable RAM alias remains within the option ROM window. A privileged guest user on a Q35/KVM machine can position this alias over locked SMRAM, bypassing chipset D_LCK protection and injecting code into System Management Mode memory.

A flaw was found in flatpak-builder where Git hooks are not disabled when applying patch sources with use-git-am: true. An attacker who can provide a malicious source containing a Git post-applypatch hook can cause the hook to execute on the host during the build process, resulting in arbitrary code execution with the privileges of the user running flatpak-builder.

A flaw was found in the file-psd plugin in GIMP. When generating a thumbnail preview for a specially crafted PSD (Photoshop Document) image file, an integer overflow occurs during the multiplication of values from an embedded JPEG header. This leads to an undersized heap allocation, resulting in a heap-based buffer overflow when the image data is decoded. This buffer overflow corrupts adjacent heap objects, allowing for a controlled memory write that can result in an application crash or arbitrary code execution.

A flaw was found in tftp-hpa. When the `in.tftpd` remap engine processes an inverse remap rule that also aborts with a non-empty custom error message, it can pass invalid match offsets to the `genmatchstring()` function. This leads to out-of-bounds read/write operations. A remote, unauthenticated attacker can exploit this vulnerability by sending a specially crafted request, causing the daemon to crash and resulting in a denial of service.

A flaw was found in environment-modules. A local attacker can exploit this vulnerability by placing a maliciously named modulefile in a location visible to the victim's `MODULEPATH`. When the victim uses Bash completion for `module` or `ml` commands, the malicious module name, containing shell metacharacters, is evaluated as a command. This can lead to arbitrary command execution in the completing user's shell, impacting their confidentiality, integrity, and availability.