Ubuntu security

USN-4994-2: Apache HTTP Server vulnerabilities USN-4994-1 fixed several vulnerabilities in Apache. This update provides the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM. Original advisory details: Antonio Morales discovered that the Apache mod_auth_digest module incorrectly handled certain Digest nonces. A remote attacker could possibly use this issue to cause Apache to crash, resulting in a denial of service. (CVE-2020-35452) Antonio Morales discovered that the Apache mod_session module incorrectly handled certain Cookie headers. A remote attacker could possibly use this issue to cause Apache to crash, resulting in a denial of service. (CVE-2021-26690) Christophe Jaillet discovered that the Apache mod_session module incorrectly handled certain SessionHeader values. A remote attacker could use this issue to cause Apache to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-26691) Christoph Anton Mitterer discovered that the new MergeSlashes configuration [ more… ]

USN-4994-1: Apache HTTP Server vulnerabilities Marc Stern discovered that the Apache mod_proxy_http module incorrectly handled certain requests. A remote attacker could possibly use this issue to cause Apache to crash, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04. (CVE-2020-13950) Antonio Morales discovered that the Apache mod_auth_digest module incorrectly handled certain Digest nonces. A remote attacker could possibly use this issue to cause Apache to crash, resulting in a denial of service. (CVE-2020-35452) Antonio Morales discovered that the Apache mod_session module incorrectly handled certain Cookie headers. A remote attacker could possibly use this issue to cause Apache to crash, resulting in a denial of service. (CVE-2021-26690) Christophe Jaillet discovered that the Apache mod_session module incorrectly handled certain SessionHeader values. A remote attacker could use this issue to cause Apache to crash, [ more… ]

USN-4993-1: Dovecot vulnerabilities Kirin discovered that Dovecot incorrectly escaped kid and azp fields in JWT tokens. A local attacker could possibly use this issue to validate tokens using arbitrary keys. This issue only affected Ubuntu 20.10 and Ubuntu 21.04. (CVE-2021-29157) Fabian Ising and Damian Poddebniak discovered that Dovecot incorrectly handled STARTTLS when using the SMTP submission service. A remote attacker could possibly use this issue to inject plaintext commands before STARTTLS negotiation. (CVE-2021-33515) Source: USN-4993-1: Dovecot vulnerabilities

USN-4992-1: GRUB 2 vulnerabilities Máté Kukri discovered that the acpi command in GRUB 2 allowed privileged users to load crafted ACPI tables when secure boot is enabled. An attacker could use this to bypass UEFI Secure Boot restrictions. (CVE-2020-14372) Chris Coulson discovered that the rmmod command in GRUB 2 contained a use- after-free vulnerability. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-25632) Chris Coulson discovered that a buffer overflow existed in the command line parser in GRUB 2. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-27749) It was discovered that the cutmem command in GRUB 2 did not honor secure boot locking. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-27779) It was discovered [ more… ]

USN-4991-1: libxml2 vulnerabilities Yunho Kim discovered that libxml2 incorrectly handled certain error conditions. A remote attacker could exploit this with a crafted XML file to cause a denial of service, or possibly cause libxml2 to expose sensitive information. This issue only affected Ubuntu 14.04 ESM, and Ubuntu 16.04 ESM. (CVE-2017-8872) Zhipeng Xie discovered that libxml2 incorrectly handled certain XML schemas. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 14.04 ESM, Ubuntu 16.04 ESM, and Ubuntu 18.04 LTS. (CVE-2019-20388) It was discovered that libxml2 incorrectly handled invalid UTF-8 input. A remote attacker could possibly exploit this with a crafted XML file to cause libxml2 to crash, resulting in a denial of service. This issue only affected Ubuntu 14.04 ESM, Ubuntu 16.04 ESM, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu [ more… ]