Resource exhaustion in Isc Bind
CVE-2023-2828
Every `named` instance configured to run as a recursive resolver maintains a cache database holding the responses to the queries it has recently sent to authoritative servers. The size limit for that cache database can be configured using the `max-cache-size` statement in the configuration file; it defaults to 90% of the total amount of memory available on the host. When the size of the cache reaches 7/8 of the configured limit, a cache-cleaning algorithm starts to remove expired and/or least-recently used RRsets from the cache, to keep memory use below the configured limit. It has been discovered that the effectiveness of the cache-cleaning algorithm used in `named` can be severely diminished by querying the resolver for specific RRsets in a certain order, effectively allowing the configured `max-cache-size` limit to be significantly exceeded. This issue affects BIND 9 versions 9.11.0 through 9.16.41, 9.18.0 through 9.18.15, 9.19.0 through 9.19.13, 9.11.3-S1 through 9.16.41-S1, and 9.18.11-S1 through 9.18.15-S1.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.038 (89.6th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 90th percentile — 89.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.038 · newest: 0.038 · change: 0.000
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- kb.isc.org/docs/cve-2023-2828 (vendor-advisory, Vendor Advisory)
- www.openwall.com/lists/oss-security/2023/06/21/6 (Patch, Mailing List, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (Mailing List, Third Party Advisory)
- www.debian.org/security/2023/dsa-5439 (Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (Mailing List, Third Party Advisory)
- security.netapp.com/advisory/ntap-20230703-0010/ (Third Party Advisory)
- lists.debian.org/debian-lts-announce/2023/07/msg00021.html (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2023-2828?
- CVE-2023-2828 is a high-severity vulnerability in Isc Bind, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2023-06-21.
- How severe is CVE-2023-2828?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2023-2828 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.