RHSA-2026:90994 — Security Advisory

An update for the go-toolset:rhel8 module is now available for Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support and Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On.

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.

Go Toolset provides the Go programming language tools and libraries. Go is alternatively known as golang.

Security Fix(es):

• golang: net/http: net/http: sensitive headers incorrectly sent after cross-domain redirect (CVE-2024-45336)

• crypto/internal/nistec: golang: Timing sidechannel for P-256 on ppc64le in crypto/internal/nistec (CVE-2025-22866)

• crypto/x509: Usage of ExtKeyUsageAny disables policy validation in crypto/x509 (CVE-2025-22874)

• crypto/tls: crypto/tls: Incorrect certificate validation during TLS session resumption (CVE-2025-68121)

• crypto/x509: Incorrect enforcement of email constraints in crypto/x509 (CVE-2026-27137)

• crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation (CVE-2026-32281)

• crypto/x509: golang: Go crypto/x509: Certificate validation bypass due to incorrect DNS constraint application (CVE-2026-33810)

• golang: internal/syscall/unix: Root.Chmod can follow symlinks out of the root (CVE-2026-32282)

• crypto/tls: golang: Go crypto/tls: Denial of Service via multiple TLS 1.3 key update messages (CVE-2026-32283)

• crypto/x509: crypto/tls: golang: Go: Denial of Service vulnerability in certificate chain building (CVE-2026-32280)

• golang: cmd/compile: no-op interface conversion bypasses overlap checking (CVE-2026-27144)

• golang: cmd/compile: possible memory corruption after bound check elimination (CVE-2026-27143)

• net/mail: golang: net/mail: Denial of Service via pathological email address parsing (CVE-2026-42499)

• 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)

• golang.org/x/net/idna: golang: net/http: golang.org/x/net/idna: Privilege escalation via incorrect Punycode label processing (CVE-2026-39821)

• mime: golang: Golang MIME: Denial of Service via maliciously-crafted MIME header (CVE-2026-42504)

• crypto/x509: golang: golang crypto/x509: Denial of Service via excessive processing of DNS SAN entries (CVE-2026-27145)

• encoding/asn1: golang: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal (CVE-2026-33818)

• net/url: golang: golang net/url: Denial of Service from quadratic complexity in path resolution (CVE-2026-56860)

• net/http: golang: Go net/http: Unencrypted HTTP/2 connections vulnerable to Denial of Service (CVE-2026-56853)

• html/template: golang: Go html/template: Cross-Site Scripting via pathological input (CVE-2026-56858)

• crypto/tls: golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages (CVE-2026-56862)

• encoding/xml: golang: Go: Denial of Service via XML decoding recursion depth issue (CVE-2026-56859)

• net/http: golang: golang: Denial of Service via crafted HTTP Range headers (CVE-2026-78667)

• crypto/tls: golang: crypto/tls: Denial of Service via multiple ECH outer extension references (CVE-2026-97031)

• net/http: net/http/internal/http2: golang.org/x/net/http2: net/http: Denial of Service via excessive HTTP/2 SETTINGS frames (CVE-2026-78669)

• crypto/x509: golang: crypto/x509: Man-in-the-middle attacks via untrusted intermediate certificates (CVE-2026-111943)

Bug Fix(es) and Enhancement(s):

• go-toolset:rhel8/golang:Update Go to version 1.26.10[rhel-8.4.z] (JIRA:RHEL-192031)

• Rebase delve with golang 1.26.10 (JIRA:RHEL-238407)

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.