RHSA-2026:98454 - Security Advisory

Topic

An update for grafana is now available for Red Hat Enterprise Linux 9.

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

Grafana is an open source, feature rich metrics dashboard and graph editor for Graphite, InfluxDB & OpenTSDB.

Security Fix(es):

• grafana: Grafana: Privilege escalation via dashboard overwrite (CVE-2026-33377)
• grafana: Grafana Auth Proxy: Unauthorized access due to incorrect IPv6 allow-list default (CVE-2026-33376)
• grafana: Grafana: Denial of Service via unbounded memory growth in OAuth login route (CVE-2026-8609)
• grafana: Grafana: Denial of Service via excessive memory allocation from large API request payloads (CVE-2026-33382)
• 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)
• grafana: PLUGIN ARCHIVE EXTRACTION ESCAPES THE PLUGIN DIRECTORY, ALLOWING CODE EXECUTION (CVE-2026-15815)
• 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/textproto: mime/multipart: golang: golang: Denial of Service via memory limit bypass in multipart form parsing (CVE-2026-94440)
• 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)

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 9 x86_64
• Red Hat Enterprise Linux for IBM z Systems 9 s390x
• Red Hat Enterprise Linux for Power, little endian 9 ppc64le
• Red Hat Enterprise Linux for ARM 64 9 aarch64

Fixes

• BZ - 2477246 - CVE-2026-33377 grafana: Grafana: Privilege escalation via dashboard overwrite
• BZ - 2477262 - CVE-2026-33376 grafana: Grafana Auth Proxy: Unauthorized access due to incorrect IPv6 allow-list default
• BZ - 2499061 - CVE-2026-8609 grafana: Grafana: Denial of Service via unbounded memory growth in OAuth login route
• BZ - 2499062 - CVE-2026-33382 grafana: Grafana: Denial of Service via excessive memory allocation from large API request payloads
• 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 - 2527474 - CVE-2026-15815 grafana: PLUGIN ARCHIVE EXTRACTION ESCAPES THE PLUGIN DIRECTORY, ALLOWING CODE EXECUTION
• BZ - 2548334 - CVE-2026-78667 net/http: golang: golang: Denial of Service via crafted HTTP Range headers
• BZ - 2548336 - CVE-2026-97031 crypto/tls: golang: crypto/tls: Denial of Service via multiple ECH outer extension references
• BZ - 2548341 - CVE-2026-94440 net/textproto: mime/multipart: golang: golang: Denial of Service via memory limit bypass in multipart form parsing
• BZ - 2548344 - CVE-2026-78669 net/http: net/http/internal/http2: golang.org/x/net/http2: net/http: Denial of Service via excessive HTTP/2 SETTINGS frames
• BZ - 2556068 - CVE-2026-111943 crypto/x509: golang: crypto/x509: Man-in-the-middle attacks via untrusted intermediate certificates

CVEs

• CVE-2026-8609
• CVE-2026-15815
• CVE-2026-33376
• CVE-2026-33377
• CVE-2026-33382
• CVE-2026-33818
• CVE-2026-56853
• CVE-2026-56858
• CVE-2026-56859
• CVE-2026-56860
• CVE-2026-56862
• CVE-2026-78667
• CVE-2026-78669
• CVE-2026-94440
• CVE-2026-97031
• CVE-2026-111943

References

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