How severe is CVE-2026-42586?

CVE-2026-42586 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability none.

Is CVE-2026-42586 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42586?

CVE-2026-42586 affects Netty. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42586?

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

Does CVE-2026-42586 have an EU (EUVD) identifier?

Yes. CVE-2026-42586 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-30129.

When was CVE-2026-42586 published?

CVE-2026-42586 was published on 2026-05-13 and last updated on 2026-06-17.

CVE-2026-42586

CVE-2026-42586 is a medium-severity vulnerability in Netty with a CVSS 3.x base score of 6.8. 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-93.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-30129
Weakness: CWE-93
Affected product: Netty
Published: 2026-05-13
Last modified: 2026-06-17

Description

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, the Netty Redis codec encoder (RedisEncoder) writes user-controlled string content directly to the network output buffer without validating or sanitizing CRLF (\r\n) characters. Since the Redis Serialization Protocol (RESP) uses CRLF as the command/response delimiter, an attacker who can control the content of a Redis message can inject arbitrary Redis commands or forge fake responses. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

Frequently asked questions

What is CVE-2026-42586?: Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, the Netty Redis codec encoder (RedisEncoder) writes user-controlled string content directly to the network output buffer without validating or sanitizing CRLF (\r\n) characters. Since the Redis Serialization Protocol (RESP) uses CRLF as the command/response delimiter, an attacker who can control the content of a Redis message can inject arbitrary Redis commands or forge fake responses. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
How severe is CVE-2026-42586?: CVE-2026-42586 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability none.
Is CVE-2026-42586 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42586?: CVE-2026-42586 affects Netty. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42586?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-42586 have an EU (EUVD) identifier?: Yes. CVE-2026-42586 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-30129.
When was CVE-2026-42586 published?: CVE-2026-42586 was published on 2026-05-13 and last updated on 2026-06-17.

References

https://github.com/netty/netty/security/advisories/GHSA-rgrr-p7gp-5xj7

Affected products (1)

cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*

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