NULL pointer dereference in Isc Dhcp

CVE-2022-2928

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.

EPSS: 0.007 (48.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2022-2928?
CVE-2022-2928 is a medium-severity vulnerability in Isc Dhcp, classified under NULL Pointer Dereference. CVSS score: 6.5/10. Published 2022-10-07.
How severe is CVE-2022-2928?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2022-2928 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.