Red Hat Red Hat Enterprise Linux 9 vulnerabilities

CVE-2026-11787 Medium · 6.3 CWE-126 Jun 9, 2026

389-ds-base: 389-ds-base: heap buffer over-read in ldap_utf8prev() via str2simple filter parsing

A flaw was found in 389 Directory Server. The ldap_utf8prev() function reads bytes before the start of a buffer without bounds checking, causing a heap buffer over-read in string filter parsing that may influence internal filter processing behavior.

CVE-2026-11786 Medium · 6.5 CWE-125 Jun 9, 2026

389-ds-base: 389-ds-base: heap out-of-bounds read in ldif parser str2entry_state_information_from_type()

A flaw was found in 389 Directory Server. The LDIF parser reads past the end of a heap buffer when processing attribute types with trailing semicolons during database import, causing an out-of-bounds read detectable under memory instrumentation.

CVE-2026-11785 Medium · 4.3 CWE-843 Jun 9, 2026

389-ds-base: 389-ds-base: partial stack address information leak via ber_printf type confusion in sso token handler

A flaw was found in 389 Directory Server. A type confusion in the SSO token extended operation handler causes partial stack address information to be disclosed in LDAP responses to authenticated users.

CVE-2026-11788 High · 7.5 CWE-476 Jun 9, 2026

389-ds-base: 389-ds-base: null pointer dereference in deref control plugin ber parser

A flaw was found in 389 Directory Server. The dereference control plugin does not check for allocation failure before using a BER structure, allowing an unauthenticated remote attacker to crash the LDAP server when the system is under memory pressure.

CVE-2026-11611 Medium · 6.5 CWE-400 Jun 8, 2026

389-ds-base: 389-ds-base: content sync plugin unbounded queue growth and race conditions

A flaw was found in 389 Directory Server. The Content Synchronization persistent search plugin allows unbounded memory growth when an authenticated client stops reading sync responses, enabling denial of service. Additional race conditions in plugin thread lifecycle can cause crashes during connection teardown or shutdown.

CVE-2026-50264 High · 7.8 CWE-787 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: out-of-bounds heap write in dri2 drigetbuffers/drigetbufferswithformat

An out-of-bounds write flaw was found in the X.Org X server and Xwayland in DRIGetBuffers/DRIGetBuffersWithFormat. A client that requests multiple DRI2BufferBackLeft attachments and one DRI2BufferFrontLeft can trigger an out-of-bounds heap write. This may be used to crash the server, or for privilege escalation if the X server runs as root.

CVE-2026-50263 Medium · 5.5 CWE-416 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: use-after-free information disclosure in createsaverwindow()

A use-after-free flaw was found in the X.Org X server and Xwayland in CreateSaverWindow(). A client can trigger a use-after-free read after changing window attributes and forcing the screen saver, leading to information disclosure.

CVE-2026-50262 Medium · 5.5 CWE-125 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: out-of-bounds read/write in glx changedrawableattributes

An out-of-bounds read flaw was found in the X.Org X server and Xwayland in __glXDisp_ChangeDrawableAttributes(). A wrong size validation check can read a client-controlled number of bytes, exceeding the request buffer, leading to information disclosure. A write path also exists but requires byte-swapped clients which is disabled by default.

CVE-2026-50261 High · 7.8 CWE-416 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: use-after-free in syncchangecounter()

A use-after-free flaw was found in the X.Org X server and Xwayland in SyncChangeCounter(). A client that sets up multiple SyncCounters can trigger a use-after-free when destroying those counters via a second client connection while changing those counters. This may be used to crash the server, or for privilege escalation if the X server runs as root.

CVE-2026-50260 High · 7.8 CWE-416 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: use-after-free in freecounter()

A use-after-free flaw was found in the X.Org X server and Xwayland in FreeCounter(). A client that sets up multiple SyncCounters and awaits on those triggers can trigger a use-after-free when destroying those counters via a second client connection. This may be used to crash the server, or for privilege escalation if the X server runs as root.

CVE-2026-50259 High · 7.8 CWE-121 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: stack buffer overflow in xkb setmap request via mapwidths indexing

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. _XkbSetMapChecks() declares a fixed-size stack buffer mapWidths[256] indexed by key type index. The helper function CheckKeyTypes() writes to this buffer at a client-controlled offset, allowing a stack buffer overflow. This may be used to crash the server, or for privilege escalation if the X server runs as root.

CVE-2026-50258 High · 7.8 CWE-121 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: stack buffer overflow in xkb key types due to unchecked shift levels

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. The X server has multiple stack buffers sized XkbMaxShiftLevel * XkbNumKbdGroups but CheckKeyTypes() does not verify or clamp non-canonical key types to XkbMaxShiftLevel. A client can change key types to excessive shift levels and trigger stack overflows. This is caused by an incomplete fix of CVE-2025-26597. This may be used to crash the server, or for privilege escalation if the X server runs as root.

CVE-2026-50257 High · 7.8 CWE-416 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: use-after-free in misyncdestroyfence()

A use-after-free flaw was found in the X.Org X server and Xwayland in miSyncDestroyFence(). A client that sets up multiple fence triggers can trigger a use-after-free function pointer call. An attacker would connect to the X server to set up a fence and await that fence, then a second X connection destroys the fence, causing the use-after-free. This may be used to crash the server, or for privilege escalation if the X server runs as root.

CVE-2026-50256 High · 7.8 CWE-121 Jun 5, 2026

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: stack buffer overflow in font alias resolution due to libxfont2 name length mismatch

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. A mismatch between the X server and the libXfont2 library's maximum font name length can cause a stack buffer overflow during font alias resolution. The server allocates a 256 byte stack buffer but libXfont2's alias target name length is 1024 bytes. A font alias name between 257 and 1023 bytes causes the X server to copy that name into the undersized stack buffer without further checks. This may be used to crash the server, or for privilege escalation if the X server runs as root.

CVE-2026-11332 High · 7.8 CWE-88 Jun 5, 2026

Ansible-core: argument injection in ansible-galaxy role install leads to arbitrary code execution

A flaw was found in ansible-core. The ansible-galaxy role install command processes dependency specifications from a role's meta/requirements.yml file. Due to improper neutralization of argument delimiters, a malicious role author can inject arbitrary git configuration flags through the src field. This allows arbitrary code execution on the machine of a user who installs the role via ansible-galaxy role install.

CVE-2026-10805 Medium · 6.7 CWE-78 Jun 4, 2026

Networkmanager: networkmanager: local privilege escalation via malformed mud urls in dhclient backend

A flaw was found in NetworkManager. This local privilege escalation vulnerability exists in NetworkManager's dhclient backend when processing malformed Manufacturer Usage Description (MUD) URLs. A local user can exploit this flaw to escalate privileges by triggering a script via a crafted MUD URL, provided an administrator has explicitly configured NetworkManager to use dhclient. This issue does not affect default configurations of NetworkManager.

CVE-2026-5419 Low · 3.7 CWE-208 Jun 1, 2026

Gnutls: gnutls: information disclosure via timing side-channel in pkcs#7 padding removal

A flaw was found in gnutls. The PKCS#7 padding check, performed during decryption, was not constant-time. This timing side-channel could allow a remote attacker to potentially leak sensitive information about the padding bytes through observable timing differences. This vulnerability is a form of information disclosure.

CVE-2026-43958 High · 7.8 CWE-121 Jun 1, 2026

Rrdtool: rrdtool: stack buffer overflow allows local code execution or denial of service

A flaw was found in rrdcached, a component of rrdtool. A local attacker with access to a rrdcached socket can exploit a stack-based buffer overflow by sending an oversized CREATE request. This vulnerability can lead to a denial of service by crashing the daemon or potentially allow for arbitrary code execution, impacting the integrity and confidentiality of data.

CVE-2026-10118 High · 7.8 CWE-190 Jun 1, 2026

Poppler: integer overflow in poppler splashoutputdev::tilingpatternfill leads to heap buffer overflow via unchecked dimension multiplication

A flaw was found in Poppler's Splash backend. A remote attacker could exploit this vulnerability by crafting a malicious PDF file that, when rendered, triggers an integer overflow in the `tilingPatternFill` function. This overflow leads to an undersized heap memory allocation, allowing a subsequent out-of-bounds write. Successful exploitation could result in arbitrary code execution, information disclosure, or denial of service within the context of the application processing the PDF.

CVE-2026-10028 Medium · 4.3 CWE-835 May 28, 2026

Glib-networking: infinite loop in glib-networking gnutls backend allows remote denial of service via circular certificate chain

A flaw was found in glib-networking. A remote attacker can exploit this vulnerability by presenting a specially crafted certificate chain to an application that uses glib-networking with the GnuTLS backend enabled and performs certificate verification. This crafted chain, which contains circular issuer relationships, can cause an infinite loop during certificate verification. The unbounded traversal consumes excessive CPU resources, leading to a denial of service for the affected process or worker.

CVE-2026-4408 Critical · 9.8 CWE-78 May 28, 2026

Samba: remote code execution in samr

A flaw was found in Samba. A remote attacker can exploit a misconfiguration in Samba file servers and classic domain controllers that use the "check password script" feature. If this script is configured with the %u substitution character, the client-controlled username is passed without proper escaping of shell meta-characters. This vulnerability allows an attacker to achieve remote command execution on the affected system. This issue primarily affects non-standard configurations where the "check password script" is used with %u and the samba-dcerpcd service is started as a system service.

CVE-2026-2340 Medium · 6.5 CWE-280 May 27, 2026

Samba: vfs_worm does not block directory modification

A flaw was found in Samba’s vfs_worm module. The module is intended to provide write-once, read-many (WORM) protections by preventing modification of files after a configurable grace period. Due to insufficient validation during rename operations, an authenticated user with write access to a share could overwrite a protected file by renaming a newly created file over the existing WORM-protected file.

CVE-2026-1933 Medium · 6.5 CWE-284 May 27, 2026

Samba: missing access check on reparse point operations

A flaw was found in Samba’s handling of NTFS-style reparse points on shares configured with read only = yes. Due to missing SMB-layer access checks, authenticated users with underlying filesystem write permissions may create or delete reparse point metadata through SMB operations even on read-only exports. This could allow modification of SMB-visible file behavior, including converting files into symbolic links or other reparse point types.

CVE-2026-3012 Medium · 6.8 CWE-345 May 27, 2026

Samba: group policy certificate enrollment uses http:// without validation

A flaw was found in Samba’s certificate auto-enrollment Group Policy handling. When certificate auto-enrollment is enabled, Samba may retrieve a CA certificate over an unencrypted HTTP connection and install it into the local trust store without proper verification. An attacker with the ability to intercept or redirect network traffic could exploit this behavior to supply a malicious certificate authority certificate, potentially allowing interception or spoofing of trusted communications.

CVE-2026-5260 High · 8.2 CWE-126 May 26, 2026

Gnutls: gnutls: information disclosure via heap overread in rsa key exchange

A flaw was found in libgnutls. A remote attacker, by sending an extremely short premaster secret during an RSA key exchange to a server using an RSA key backed by a PKCS#11 token, could trigger a short heap overread. This memory corruption vulnerability could lead to information disclosure.