CVE-2026-6238

Name: CVE-2026-6238
Creator: NVD / NIST
Published: 2026-04-28T19:37:47.523+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.31%

Last modified Jun 19, 2026

CVE-2026-6238 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.0.1 to version 2.43 fail to validate the RDATA content against the RDATA length in a DNS response when processing A6, CERT, LOC, 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. EPSS estimates a 0.31% chance of exploitation in the next 30 days.

Description

The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.0.1 to version 2.43 fail to validate the RDATA content against the RDATA length in a DNS response when processing A6, CERT, LOC, 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.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L

EPSS Probability

0.31%

22.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-126

Affected Software

Vendor	Product	Versions
Gnu	Glibc	>= 2.2

References

https://inbox.sourceware.org/libc-announce/7a655d55-276f-41fe-b550-feb3ebb2ce91@redhat.com/T/#uThird Party Advisory
https://sourceware.org/bugzilla/show_bug.cgi?id=34069Issue Tracking

Timeline

Published: Apr 28, 2026
Last Modified: Jun 19, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2026-6238?

How severe is CVE-2026-6238?

CVE-2026-6238 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.31% probability of exploitation in the next 30 days.

How do I fix CVE-2026-6238?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-6238?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST