CVE-2022-2928

The Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on UDP/IP networks whereby a DHCP server dynamically assigns an IP address and other network configuration parameters to each device on a network so they can communicate with other IP networks.

Security Fix(es):

In ISC DHCP 4.4.0 -> 4.4.3, ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16-P1, when the function option_code_hash_lookup() is called from add_option(), it increases the option's refcount field. However, there is not a corresponding call to option_dereference() to decrement the refcount field. The function add_option() is only used in server responses to lease query packets. Each lease query response calls this function for several options, so eventually, the reference counters could overflow and cause the server to abort.(CVE-2022-2928)

In ISC DHCP 1.0 -> 4.4.3, ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16-P1 a system with access to a DHCP server, sending DHCP packets crafted to include fqdn labels longer than 63 bytes, could eventually cause the server to run out of memory.(CVE-2022-2929)

In ISC DHCP 4.4.0 -> 4.4.3, ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16-P1, when the function option_code_hash_lookup() is called from add_option(), it increases the option's refcount field. However, there is not a corresponding call to option_dereference() to decrement the refcount field. The function add_option() is only used in server responses to lease query packets. Each lease query response calls this function for several options, so eventually, the reference counters could overflow and cause the server to abort.

The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address. The dhcp packages provide a relay agent and ISC DHCP service required to enable and administer DHCP on a network.

Security Fix(es):

• dhcp: option refcount overflow when leasequery is enabled leading to dhcpd abort (CVE-2022-2928)
• dhcp: DHCP memory leak (CVE-2022-2929)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address. The dhcp packages provide a relay agent and ISC DHCP service required to enable and administer DHCP on a network.

Security Fix(es):

• dhcp: option refcount overflow when leasequery is enabled leading to dhcpd abort (CVE-2022-2928)
• dhcp: DHCP memory leak (CVE-2022-2929)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

• SECURITY UPDATE: option refcount overflow
  • debian/patches/CVE-2022-2928.patch: fix work with reference counter 'refcount'
  • CVE-2022-2928
• SECURITY UPDATE: DHCP memory leak
  • debian/patches/CVE-2022-2929.patch: free memory when incorrect 'fqdn' labels are used
  • CVE-2022-2929

• CVE-2022-2928: option refcount overflow when leasequery is enabled leading to dhcpd abort
• CVE-2022-2929: DHCP memory leak
• Backported tests from upstream, for this and other CVE`s

• CVE-2022-2928: option refcount overflow when leasequery is enabled leading to dhcpd abort
• CVE-2022-2929: DHCP memory leak
• Backported tests from upstream, for this and other CVE`s

In ISC DHCP 4.4.0 -> 4.4.3, ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16-P1, when the function option_code_hash_lookup() is called from add_option(), it increases the option's refcount field. However, there is not a corresponding call to option_dereference() to decrement the refcount field. The function add_option() is only used in server responses to lease query packets. Each lease query response calls this function for several options, so eventually, the reference counters could overflow and cause the server to abort.

In ISC DHCP 4.4.0 -> 4.4.3, ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16-P1, when the function option_code_hash_lookup() is called from add_option(), it increases the option's refcount field. However, there is not a corresponding call to option_dereference() to decrement the refcount field. The function add_option() is only used in server responses to lease query packets. Each lease query response calls this function for several options, so eventually, the reference counters could overflow and cause the server to abort. (CVE-2022-2928)

In ISC DHCP 1.0 -> 4.4.3, ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16-P1 a system with access to a DHCP server, sending DHCP packets crafted to include fqdn labels longer than 63 bytes, could eventually cause the server to run out of memory. (CVE-2022-2929)

These are all security issues fixed in the dhcp-4.4.2.P1-11.1 package on the GA media of openSUSE Tumbleweed.

This update for dhcp fixes the following issues:

• CVE-2022-2928: Fixed an option refcount overflow (bsc#1203988).
• CVE-2022-2929: Fixed a DHCP memory leak (bsc#1203989).

This update for dhcp fixes the following issues:

• CVE-2022-2928: Fixed an option refcount overflow (bsc#1203988).
• CVE-2022-2929: Fixed a DHCP memory leak (bsc#1203989).

It was discovered that DHCP incorrectly handled option reference counting. A remote attacker could possibly use this issue to cause DHCP servers to crash, resulting in a denial of service. (CVE-2022-2928)

It was discovered that DHCP incorrectly handled certain memory operations. A remote attacker could possibly use this issue to cause DHCP clients and servers to consume resources, leading to a denial of service. (CVE-2022-2929)

USN-5658-1 fixed vulnerabilities in DHCP. This update provides the corresponding updates for Ubuntu 16.04 ESM.

Original advisory details:

It was discovered that DHCP incorrectly handled option reference counting. A remote attacker could possibly use this issue to cause DHCP servers to crash, resulting in a denial of service. (CVE-2022-2928)

It was discovered that DHCP incorrectly handled certain memory operations. A remote attacker could possibly use this issue to cause DHCP clients and servers to consume resources, leading to a denial of service. (CVE-2022-2929)

USN-5658-1 fixed several vulnerabilities in DHCP. This update provides the corresponding update for Ubuntu 14.04 ESM.

Original advisory details:

It was discovered that DHCP incorrectly handled option reference counting. A remote attacker could possibly use this issue to cause DHCP servers to crash, resulting in a denial of service. (CVE-2022-2928)

It was discovered that DHCP incorrectly handled certain memory operations. A remote attacker could possibly use this issue to cause DHCP clients and servers to consume resources, leading to a denial of service. (CVE-2022-2929)