crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks (CVE-2026-64208) | HOL Guard CVE

High · CVSS 7.5CVE-2026-64208

crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks

Answer in brief

CVE-2026-64208 records a High severity (CVSS 7.5) vulnerability in crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (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 Jul 24, 2026Updated Aug 12, 2026Source checked Sep 21, 2026First seen by HOL Aug 5, 2026Material review Aug 12, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 7 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 7.5. 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 Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Affected products and reported versions
Product	Affected versions	Fixed versions
cpe:2.3:o:linux:linux_kernel::::::::	Not reported	Not reported
cpe:2.3:o:linux:linux_kernel:7.1:rc1::::::	Not reported	Not reported
cpe:2.3:o:linux:linux_kernel:7.1:rc2::::::	Not reported	Not reported
cpe:2.3:o:linux:linux_kernel:7.1:rc3::::::	Not reported	Not reported
cpe:2.3:o:linux:linux_kernel:7.1:rc4::::::	Not reported	Not reported

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a <585f9f6aef5c4542ac9d6ec45cd7dbc7df9af3ff \|\| >=9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a <9217017f4bce53dddb8d547837f1f707045d64ad \|\| >=9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a <2b50aceafe6606ea52ed42aadd1b4d44a188aade	585f9f6aef5c4542ac9d6ec45cd7dbc7df9af3ff, 9217017f4bce53dddb8d547837f1f707045d64ad, 2b50aceafe6606ea52ed42aadd1b4d44a188aade
Linux/Linuxgeneric	6.16	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 585f9f6aef5c4542ac9d6ec45cd7dbc7df9af3ff if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jul 24, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 12, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 5, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks Change the krb5 crypto library to provide facilities to precheck the length of the message about to be decrypted or verified. Fix AF_RXRPC to make use of this to validate DATA packets secured with RxGK.

Quoted source text, attributed separately from HOL analysis.