Bug#1135231: glibc: CVE-2026-6238

Source: glibc
Version: 2.42-15
Severity: important
Tags: security upstream
Forwarded: https://sourceware.org/bugzilla/show_bug.cgi?id=34069
X-Debbugs-Cc: [email protected], Debian Security Team <[email protected]>

Hi,

The following vulnerability was published for glibc, filling mainly
for tracking.

CVE-2026-6238[0]:
| The deprecated functions ns_printrrf, ns_printrr and fp_nquery in
| the GNU C Library version 2.2 and newer fail to validate the RDATA
| content against the RDATA length in a DNS response when processing
| LOC, CERT, TKEY or TSIG records, which may allow an attacker to
| craft a DNS response, causing a target application to crash or read
| uninitialized memory.  These functions are for application debugging
| only and hence not in the path of code executed by the DNS resolver.
| Further, they have been deprecated since version 2.34 and should not
| be used by any new applications.  Applications should consider
| porting away from these interfaces since they may be removed in
| future versions.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-6238
    https://www.cve.org/CVERecord?id=CVE-2026-6238
[1] https://sourceware.org/bugzilla/show_bug.cgi?id=34069
[2] https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0012

Regards,
Salvatore