RHSA-2026:87246 - Security Advisory

Topic

An update for the go-toolset:rhel8 module is now available for Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support and Red Hat Enterprise Linux 8.6 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.

Description

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)
• net/http: Sensitive headers not cleared on cross-origin redirect in net/http (CVE-2025-4673)
• 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)
• golang: crypto/x509: Go: crypto/x509: mitigation for security concerns with a specific Certificate Authority (CVE-2026-111943)

Bug Fix(es) and Enhancement(s):

• go-toolset:rhel8/golang:Update Go to version 1.25.9+2 [rhel-8.6.z] (JIRA:RHEL-192032)
• go-toolset: golang: Update Go to version 1.24.6+1 [rhel-8.6.z] (JIRA:RHEL-235970)
• Rebase delve with golang 1.26.1 (JIRA:RHEL-238405)

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 - Extended Life Cycle Long Life 8.6 x86_64
• Red Hat Enterprise Linux Server - AUS 8.6 x86_64

Fixes

• BZ - 2341751 - CVE-2024-45336 golang: net/http: net/http: sensitive headers incorrectly sent after cross-domain redirect
• BZ - 2344219 - CVE-2025-22866 crypto/internal/nistec: golang: Timing sidechannel for P-256 on ppc64le in crypto/internal/nistec
• BZ - 2372320 - CVE-2025-22874 crypto/x509: Usage of ExtKeyUsageAny disables policy validation in crypto/x509
• BZ - 2373305 - CVE-2025-4673 net/http: Sensitive headers not cleared on cross-origin redirect in net/http
• BZ - 2437111 - CVE-2025-68121 crypto/tls: crypto/tls: Incorrect certificate validation during TLS session resumption
• BZ - 2445345 - CVE-2026-27137 crypto/x509: Incorrect enforcement of email constraints in crypto/x509
• BZ - 2456333 - CVE-2026-32281 crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation
• BZ - 2456335 - CVE-2026-33810 crypto/x509: golang: Go crypto/x509: Certificate validation bypass due to incorrect DNS constraint application
• BZ - 2456336 - CVE-2026-32282 golang: internal/syscall/unix: Root.Chmod can follow symlinks out of the root
• BZ - 2456338 - CVE-2026-32283 crypto/tls: golang: Go crypto/tls: Denial of Service via multiple TLS 1.3 key update messages
• BZ - 2456339 - CVE-2026-32280 crypto/x509: crypto/tls: golang: Go: Denial of Service vulnerability in certificate chain building
• BZ - 2456340 - CVE-2026-27144 golang: cmd/compile: no-op interface conversion bypasses overlap checking
• BZ - 2456342 - CVE-2026-27143 golang: cmd/compile: possible memory corruption after bound check elimination
• BZ - 2467809 - CVE-2026-42499 net/mail: golang: net/mail: Denial of Service via pathological email address parsing
• BZ - 2467815 - CVE-2026-33814 net/http/internal/http2: golang: golang.org/x/net: Go HTTP/2: Denial of Service via malformed SETTINGS_MAX_FRAME_SIZE frame
• BZ - 2467820 - CVE-2026-39820 net/mail: golang: Go net/mail: Denial of Service via crafted email inputs
• BZ - 2467822 - CVE-2026-33811 net: golang: Go net package: Denial of Service via long CNAME response in LookupCNAME
• BZ - 2480756 - CVE-2026-39821 golang.org/x/net/idna: golang: net/http: golang.org/x/net/idna: Privilege escalation via incorrect Punycode label processing
• BZ - 2484204 - CVE-2026-42504 mime: golang: Golang MIME: Denial of Service via maliciously-crafted MIME header
• BZ - 2484207 - CVE-2026-27145 crypto/x509: golang: golang crypto/x509: Denial of Service via excessive processing of DNS SAN entries
• BZ - 2515815 - CVE-2026-33818 encoding/asn1: golang: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal
• BZ - 2515820 - CVE-2026-56860 net/url: golang: golang net/url: Denial of Service from quadratic complexity in path resolution
• BZ - 2515827 - CVE-2026-56853 net/http: golang: Go net/http: Unencrypted HTTP/2 connections vulnerable to Denial of Service
• BZ - 2515838 - CVE-2026-56858 html/template: golang: Go html/template: Cross-Site Scripting via pathological input
• BZ - 2515839 - CVE-2026-56862 crypto/tls: golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages
• BZ - 2515840 - CVE-2026-56859 encoding/xml: golang: Go: Denial of Service via XML decoding recursion depth issue
• BZ - 2556068 - CVE-2026-111943 crypto/x509: golang: crypto/x509: Man-in-the-middle attacks via untrusted intermediate certificates
• RHEL-192032 - go-toolset:rhel8/golang:Update Go to version 1.25.9+2 [rhel-8.6.z]
• RHEL-235970 - go-toolset: golang: Update Go to version 1.24.6+1 [rhel-8.6.z]
• RHEL-238405 - Rebase delve with golang 1.26.1 [rhel-8.6.0.z]

CVEs

• CVE-2024-45336
• CVE-2025-4673
• CVE-2025-22866
• CVE-2025-22874
• CVE-2025-68121
• CVE-2026-27137
• CVE-2026-27143
• CVE-2026-27144
• CVE-2026-27145
• CVE-2026-32280
• CVE-2026-32281
• CVE-2026-32282
• CVE-2026-32283
• CVE-2026-33810
• CVE-2026-33811
• CVE-2026-33814
• CVE-2026-33818
• CVE-2026-39820
• CVE-2026-39821
• CVE-2026-42499
• CVE-2026-42504
• CVE-2026-56853
• CVE-2026-56858
• CVE-2026-56859
• CVE-2026-56860
• CVE-2026-56862
• CVE-2026-56866
• CVE-2026-78659
• CVE-2026-78660
• CVE-2026-78663
• CVE-2026-78667
• CVE-2026-78669
• CVE-2026-94439
• CVE-2026-94440
• CVE-2026-94444
• CVE-2026-94447
• CVE-2026-94448
• CVE-2026-97030
• CVE-2026-97031
• CVE-2026-97032
• CVE-2026-111943

References

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