CVE-2026-5950Medium· 5.3▾ TwilightPoC availableAn unbounded resend loop vulnerability exists in the BIND 9 resolver state machine during bad-server handling, enabling a remote unauthenticated attacker to cause severe resource exhaustion by sending queries that trigger specific retry …
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 29.2 · likelihood 0.1 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Public exploit / PoC code seen in 1 source. Availability, not in-the-wild use.
Exploit-prediction probability, daily snapshots since Jul 23.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.6%
0.6% → 0.7%
1 GitHub repo
An unbounded resend loop vulnerability exists in the BIND 9 resolver state machine during bad-server handling, enabling a remote unauthenticated attacker to cause severe resource exhaustion by sending queries that trigger specific retry conditions. This issue affects BIND 9 versions 9.18.36 through 9.18.48, 9.20.8 through 9.20.22, 9.21.7 through 9.21.21, 9.18.36-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.
bind >= 9.18.36, < 9.18.49bind >= 9.20.8, < 9.20.23bind >= 9.21.7, < 9.21.21Upgrade past the affected range:
bind 9.21.21Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
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