High · CVSS 8.1CVE-2026-94300

Concurrent GSS-TSIG messages corrupt memoryCVE-2026-94300

Answer in brief

CVE-2026-94300 records a High severity (CVSS 8.1) vulnerability in Concurrent GSS-TSIG messages corrupt memory. The current sources do not mark it as known exploited. The current feed maps ISC/BIND 9 (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 21, 2026Updated Oct 21, 2026Source checked Oct 21, 2026First seen by HOL Oct 21, 2026Material review Oct 21, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.1
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 8.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps ISC/BIND 9 (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
ISC/BIND 9generic	>=9.11.0 <=9.18.50 \|\| >=9.20.0 <=9.20.29 \|\| >=9.21.0 <=9.21.26 \|\| >=9.11.3-S1 <=9.18.50-S1 \|\| >=9.20.9-S1 <=9.20.29-S1	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for ISC/BIND 9.
Review the reported fix. Source-reported solution: Upgrade to the patched release most closely related to your current version of BIND 9: 9.20.30, 9.21.27, or 9.20.30-S1.

Evidence timeline and material changes

Published upstream
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 21, 2026

Sources and claim methodology

Upstream source description

Replaying GSS-TSIG signed UDP messages can result in memory corruption in "`named`". An attacker who can capture a previously signed UDP message can replay it while the negotiated TSIG key is still valid. By also sending crafted queries to a zone the attacker controls, the attacker may potentially achieve remote code execution. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.

Quoted source text, attributed separately from HOL analysis.