CVE-2026-11622: isc bind 9
Vulnerability summary
CVE-2026-11622 is a high (CVSS 7.5) vulnerability in isc bind 9. EPSS estimates a 0.54% chance of exploitation in the next 30 days, higher than 44.4% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 22 · Related 11Timeline
- 22-07-2026PublishedVulnerability first disclosed.
- 22-07-2026Last modifiedVulnerability information updated.
Description
A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can suffer from runaway memory usage. The attacker needs to be able to send queries faster than the resolver can perform validation. The increased memory usage can be orders of magnitude beyond the limit configured in the `max-cache-size` parameter. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
CVSS metrics
5 scores · 5 sources · 1 version- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.54%
Chance of exploitation in the next 30 days
Percentile
44%
Versus all other CVEs
30-day change
+0.02 pp
From 0.52% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu3 products
- bind9All versions (No fix recorded) | < 1:9.18.30-0ubuntu0.20.04.2+esm3 | < 1:9.18.39-0ubuntu0.22.04.5 | < 1:9.18.39-0ubuntu0.24.04.6 | < 1:9.20.24-1ubuntu0.2
- bind9-libsAll versions (No fix recorded)
- isc-dhcpAll versions (No fix recorded)
Alpine1 product
- bind< 9.20.26-r0
Debian1 product
- bind9< 1:9.18.49-1~deb12u2 | < 1:9.20.26-1~deb13u1 | < 1:9.20.26-1
Isc1 product
- bind 9≥ 9.11.0, ≤ 9.18.50 | ≥ 9.20.0, ≤ 9.20.24 | ≥ 9.21.0, ≤ 9.21.23 | ≥ 9.11.3-S1, ≤ 9.18.50-S1 | ≥ 9.20.9-S1, ≤ 9.20.24-S1
4 vendors · 6 products