DEBIAN-CVE-2026-5947
Undefined behavior may result due to a race condition leading to a use-after-free violation. If BIND receives an incoming DNS message signed with SIG(0), it begins work to validate that signature. If, during that validation, the "recursive-clients" limit is reached (as would occur during a query flood), and that same DNS message is discarded per the limit, there is a brief window of time while the SIG(0) validation may attempt to read the now-discarded DNS message. This issue affects BIND 9 versions 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, and 9.20.9-S1 through 9.20.22-S1. BIND 9 versions 9.18.28 through 9.18.49 and 9.18.28-S1 through 9.18.49-S1 are NOT affected.
DEBIAN-CVE-2026-5947
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-5947
bind9
Source reference: /affected/0/package/name
- Affected versions
- 1:9.20.11-4
Source reference:
/affected/0/versions1:9.20.15-1Source reference:
/affected/0/versions1:9.20.15-1~deb13u1Source reference:
/affected/0/versions1:9.20.15-1~deb13u1~bpo12+1Source reference:
/affected/0/versions1:9.20.15-2Source reference:
/affected/0/versions1:9.20.18-1Source reference:
/affected/0/versions1:9.20.18-1~deb13u1Source reference:
/affected/0/versions1:9.20.18-1~deb13u1~bpo12+1Source reference:
/affected/0/versions1:9.20.19-1Source reference:
/affected/0/versions1:9.20.19-1~bpo12+1Source reference:
/affected/0/versions1:9.20.20-1Source reference:
/affected/0/versions1:9.20.20-1~bpo12+1Source reference:
/affected/0/versions1:9.20.21-1Source reference:
/affected/0/versions1:9.20.21-1~deb13u1Source reference:
/affected/0/versions1:9.20.21-1~deb13u1~bpo12+1Source reference:
/affected/0/versions1:9.20.22-1Source reference:
/affected/0/versions1:9.20.23-1~deb13u1~bpo12+1Source reference:
/affected/0/versions - Fixed versions
- 1:9.20.23-1~deb13u1
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
bind9
Source reference: /affected/1/package/name
- Affected versions
- 1:9.20.11-4
Source reference:
/affected/1/versions1:9.20.15-1Source reference:
/affected/1/versions1:9.20.15-1~deb13u1Source reference:
/affected/1/versions1:9.20.15-1~deb13u1~bpo12+1Source reference:
/affected/1/versions1:9.20.15-2Source reference:
/affected/1/versions1:9.20.18-1Source reference:
/affected/1/versions1:9.20.18-1~deb13u1Source reference:
/affected/1/versions1:9.20.18-1~deb13u1~bpo12+1Source reference:
/affected/1/versions1:9.20.19-1Source reference:
/affected/1/versions1:9.20.19-1~bpo12+1Source reference:
/affected/1/versions1:9.20.20-1Source reference:
/affected/1/versions1:9.20.20-1~bpo12+1Source reference:
/affected/1/versions1:9.20.21-1Source reference:
/affected/1/versions1:9.20.21-1~deb13u1Source reference:
/affected/1/versions1:9.20.21-1~deb13u1~bpo12+1Source reference:
/affected/1/versions1:9.20.22-1Source reference:
/affected/1/versions1:9.20.23-1~deb13u1Source reference:
/affected/1/versions1:9.20.23-1~deb13u1~bpo12+1Source reference:
/affected/1/versions - Fixed versions
- 1:9.20.23-1
Source reference:
/affected/1/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.20.23-1~deb13u1"
}
]
}
],
"package": {
"name": "bind9",
"purl": "pkg:deb/debian/bind9?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1:9.20.11-4",
"1:9.20.15-1",
"1:9.20.15-1~deb13u1",
"1:9.20.15-1~deb13u1~bpo12+1",
"1:9.20.15-2",
"1:9.20.18-1",
"1:9.20.18-1~deb13u1",
"1:9.20.18-1~deb13u1~bpo12+1",
"1:9.20.19-1",
"1:9.20.19-1~bpo12+1",
"1:9.20.20-1",
"1:9.20.20-1~bpo12+1",
"1:9.20.21-1",
"1:9.20.21-1~deb13u1",
"1:9.20.21-1~deb13u1~bpo12+1",
"1:9.20.22-1",
"1:9.20.23-1~deb13u1~bpo12+1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-5947.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:9.20.23-1"
}
]
}
],
"package": {
"name": "bind9",
"purl": "pkg:deb/debian/bind9?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1:9.20.11-4",
"1:9.20.15-1",
"1:9.20.15-1~deb13u1",
"1:9.20.15-1~deb13u1~bpo12+1",
"1:9.20.15-2",
"1:9.20.18-1",
"1:9.20.18-1~deb13u1",
"1:9.20.18-1~deb13u1~bpo12+1",
"1:9.20.19-1",
"1:9.20.19-1~bpo12+1",
"1:9.20.20-1",
"1:9.20.20-1~bpo12+1",
"1:9.20.21-1",
"1:9.20.21-1~deb13u1",
"1:9.20.21-1~deb13u1~bpo12+1",
"1:9.20.22-1",
"1:9.20.23-1~deb13u1",
"1:9.20.23-1~deb13u1~bpo12+1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-5947.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #58023 · Revision 1
- Added to Heist Feed
- Publisher date