RHSA-2026:22120 - Security Advisory

Topic

An update for golang is now available for Red Hat Enterprise Linux 10.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The golang packages provide the Go programming language compiler.

Security Fix(es):

• net/mail: golang: net/mail: Denial of Service via pathological email address parsing (CVE-2026-42499)
• cmd/go: golang: Go command (cmd/go): Integrity bypass due to checksum validation flaw via malicious module proxy (CVE-2026-42501)
• html/template: golang: Go html/template: Cross-Site Scripting via improper URL escaping in meta tag content (CVE-2026-39823)
• cmd/go: golang: Go 'go bug' command: Arbitrary file overwrite via symlink attack (CVE-2026-39819)
• net/http/internal/http2: golang: golang.org/x/net: Go HTTP/2: Denial of Service via malformed SETTINGS_MAX_FRAME_SIZE frame (CVE-2026-33814)
• net/mail: golang: Go net/mail: Denial of Service via crafted email inputs (CVE-2026-39820)
• net: golang: Go net package: Denial of Service via long CNAME response in LookupCNAME (CVE-2026-33811)
• net/http/httputil: golang: net/http/httputil: ReverseProxy forwards hidden query parameters, potentially bypassing security controls (CVE-2026-39825)
• cmd/go: golang: Go tool pack: Arbitrary file write via malicious archive extraction (CVE-2026-39817)
• html/template: golang: html/template: Cross-site scripting due to incorrect script tag escaping (CVE-2026-39826)
• net: golang: Go net package: Denial of Service via NUL byte in Dial and LookupPort on Windows (CVE-2026-39836)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 10 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 x86_64
• Red Hat Enterprise Linux for IBM z Systems 10 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.2 s390x
• Red Hat Enterprise Linux for Power, little endian 10 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.2 ppc64le
• Red Hat Enterprise Linux for ARM 64 10 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.2 aarch64
• Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.2 aarch64
• Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.2 s390x
• Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.2 ppc64le
• Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.2 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 10.2 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 10.2 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 10.2 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 10.2 s390x

Fixes

• BZ - 2467822 - CVE-2026-33811 net: golang: Go net package: Denial of Service via long CNAME response in LookupCNAME
• RHEL-175605 - Update Go to version 1.26.3+1 [rhel-10.2.z]

CVEs

• CVE-2026-33811
• CVE-2026-33814
• CVE-2026-39817
• CVE-2026-39819
• CVE-2026-39820
• CVE-2026-39823
• CVE-2026-39825
• CVE-2026-39826
• CVE-2026-39836
• CVE-2026-42499
• CVE-2026-42501

References

• https://access.redhat.com/security/updates/classification/#important