How severe is CVE-2026-6238?

CVE-2026-6238 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.

Is CVE-2026-6238 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-6238?

CVE-2026-6238 affects Gnu Glibc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-6238?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-6238 have an EU (EUVD) identifier?

Yes. CVE-2026-6238 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26071.

When was CVE-2026-6238 published?

CVE-2026-6238 was published on 2026-04-28 and last updated on 2026-06-19.

CVE-2026-6238

CVE-2026-6238 is a medium-severity vulnerability in Gnu Glibc with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-126.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-26071
Weakness: CWE-126
Affected product: Gnu Glibc
Published: 2026-04-28
Last modified: 2026-06-19

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.

Frequently asked questions

What is CVE-2026-6238?: 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.
How severe is CVE-2026-6238?: CVE-2026-6238 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.
Is CVE-2026-6238 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-6238?: CVE-2026-6238 affects Gnu Glibc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-6238?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-6238 have an EU (EUVD) identifier?: Yes. CVE-2026-6238 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26071.
When was CVE-2026-6238 published?: CVE-2026-6238 was published on 2026-04-28 and last updated on 2026-06-19.

References

Affected products (1)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*

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