CVE-2026-42504: Quadratic complexity in WordDecoder.DecodeHeader in mime

Awaiting analysis

AliasesRHSA-2026:57456UBUNTU-CVE-2026-42504DEBIAN-CVE-2026-42504+5135 more

Published 02-06-2026Last modified 03-11-2026

Vulnerability summary

CVE-2026-42504 is a high (CVSS 7.5) Inefficient Algorithmic Complexity vulnerability in go standard library mime. EPSS estimates a 0.56% chance of exploitation in the next 30 days, higher than 46.6% of scored vulnerabilities.

Priority

Prioritisesevere

Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?

CVSS score

7.5/10

010

High · v3.1 (CVE.org)

EPSS score

0.56%

0%100%

Low · 0.00 pp in 30 days

KEVNot listedNot listed by any tracked catalog.

RansomwareNot flaggedNo ransomware use recorded.

Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 86 · Related 86

MGASA-2026-0276 OPENSUSE-SU-2026:10959-1 OPENSUSE-SU-2026:10960-1 OPENSUSE-SU-2026:10975-1 OPENSUSE-SU-2026:12271-1 OPENSUSE-SU-2026:20976-1+81 more

Timeline

02-06-2026
PublishedVulnerability first disclosed.
03-11-2026
Last modifiedVulnerability information updated.

Description

Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.

CVSS metrics

6 scores · 6 sources · 1 version

v3.17.5

EPSS trend

Probability

0.56%

Chance of exploitation in the next 30 days

Percentile

47%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.56% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs

CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

CWE-407Inefficient Algorithmic ComplexityAn algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard199 products

aactl< 0.4.12-r54
actAll versions (No fix recorded)
actionlintAll versions (No fix recorded)
actions-runner-controller< 0.14.2-r2 | All versions (No fix recorded)
addon-resizer< 1.8.23-r20

addon-resizer-fips< 1.8.23-r19
age-fips< 1.3.1-r12 | All versions (No fix recorded)
agentbeat< 9.2.7-r12
agentbeat-fips< 9.2.7-r11
amazon-cloudwatch-agent< 1.300069.0-r2
amazon-cloudwatch-agent-amazon-cloudwatch-agent-config-wizardAll versions (No fix recorded)
amazon-cloudwatch-agent-amazon-cloudwatch-agent-config-wizard-fipsAll versions (No fix recorded)
amazon-cloudwatch-agent-config-downloaderAll versions (No fix recorded)
amazon-cloudwatch-agent-config-downloader-fipsAll versions (No fix recorded)
amazon-cloudwatch-agent-config-translatorAll versions (No fix recorded)
amazon-cloudwatch-agent-config-translator-fipsAll versions (No fix recorded)
amazon-cloudwatch-agent-fips< 1.300069.0-r2
amazon-cloudwatch-agent-operator< 3.5.0-r0
amazon-cloudwatch-agent-start-amazon-cloudwatch-agentAll versions (No fix recorded)
amazon-cloudwatch-agent-start-amazon-cloudwatch-agent-fipsAll versions (No fix recorded)
amazon-ecs-agent< 1.103.2-r1 | All versions (No fix recorded)
amazon-ecs-cni-plugins-fipsAll versions (No fix recorded) | < 2024.9.0_git20260522-r1
amazon-eks-ami< 20260527-r1 | All versions (No fix recorded)
amazon-k8s-cniAll versions (No fix recorded) | < 1.22.1-r1
amazon-k8s-cni-initAll versions (No fix recorded)
amazon-k8s-cni-init-fips-compatAll versions (No fix recorded) | < 1.22.1-r2
amazon-vpc-cni-plugins-fipsAll versions (No fix recorded) | < 1.3_git20260307-r3
ansible-operator< 1.42.2-r9
apache-exporterAll versions (No fix recorded)
apisix-ingress-controller< 2.1.0-r1
apm-server-8.19All versions (No fix recorded)
apm-server-9.2All versions (No fix recorded)
apm-server-9.3All versions (No fix recorded)
argo-cd-3.0< 3.0.23-r6
argo-cd-3.0-compat< 3.0.23-r6
argo-cd-3.1< 3.1.16-r3
argo-cd-3.1-compat< 3.1.16-r3
argo-cd-3.3-compat< 3.3.14-r9
argo-cd-fips-3.0< 3.0.23-r7
argo-cd-fips-3.0-compat< 3.0.23-r7
argo-cd-fips-3.1< 3.1.16-r1
argo-cd-fips-3.1-compat< 3.1.16-r1
argo-cd-fips-3.2< 3.2.12-r6
argo-cd-fips-3.2-compat< 3.2.12-r6
argo-cd-fips-3.3< 3.3.11-r1
argo-cd-fips-3.3-compat< 3.3.11-r1
argo-cd-fips-3.4< 3.4.3-r1
argo-cd-fips-3.4-compat< 3.4.3-r1
argo-events< 1.9.10-r25
argo-events-fips< 1.9.10-r17
argo-rollouts< 1.9.0-r15
argo-workflow-controller-3.6< 3.6.19-r7
argo-workflow-controller-fips-3.6< 3.6.19-r10
argo-workflow-controller-fips-4.0< 4.0.5-r6
argo-workflow-executor-3.6< 3.6.19-r7
argo-workflow-executor-fips-3.6< 3.6.19-r10
argo-workflow-executor-fips-3.7< 3.7.14-r5
argo-workflow-executor-fips-4.0< 4.0.5-r6
argo-workflows-3.6< 3.6.19-r7
argo-workflows-fips-3.6< 3.6.19-r10
argo-workflows-fips-4.0< 4.0.5-r6
argocd-image-updater< 1.2.1-r2
atlantisAll versions (No fix recorded)
atlantis-fipsAll versions (No fix recorded)
atlas-1.0All versions (No fix recorded)
atlas-1.2All versions (No fix recorded)
auditbeat-9.0< 9.0.8-r22
auditbeat-9.3< 9.3.5-r1
auditbeat-fips-8.19< 8.19.16-r1
auditbeat-fips-9.0< 9.0.8-r25
auditbeat-fips-9.3< 9.3.5-r1
auditbeat-fips-9.4< 9.4.2-r1
authentik-fips-2025.12-go-server< 2025.12.6-r2
authentik-fips-2026.2-go-serverAll versions (No fix recorded)
authservice< 1.1.5-r10
authservice-fips< 1.1.5-r11
avmfixAll versions (No fix recorded)
avmfix-fipsAll versions (No fix recorded)
aws-ebs-csi-driver-1.52< 1.52.1-r14
aws-ebs-csi-driver-1.53< 1.53.0-r12
aws-ebs-csi-driver-1.55< 1.55.0-r10
aws-ebs-csi-driver-1.60< 1.60.1-r3
aws-ebs-csi-driver-fips-1.51< 1.51.2-r14
aws-ebs-csi-driver-fips-1.52< 1.52.1-r14
aws-ebs-csi-driver-fips-1.54< 1.54.0-r12
aws-ebs-csi-driver-fips-1.57< 1.57.1-r5
aws-efs-csi-driver< 3.2.0-r2
aws-efs-csi-driver-fips< 3.2.0-r2
aws-flb-cloudwatchAll versions (No fix recorded)
aws-flb-cloudwatch-fips< 1.9.5-r1
aws-flb-firehose-fipsAll versions (No fix recorded)
aws-flb-kinesisAll versions (No fix recorded)
aws-flb-kinesis-fips< 1.10.4-r1
aws-fsx-csi-driver< 1.9.0-r5
aws-fsx-csi-driver-fips< 1.9.0-r5
aws-iam-authenticator-fips< 0.7.17-r1
aws-lambda-runtime-interface-emulatorAll versions (No fix recorded)
aws-lambda-runtime-interface-emulator-fipsAll versions (No fix recorded)
aws-network-policy-agent< 1.3.5-r2 | All versions (No fix recorded)
aws-node-termination-handler< 1.25.6-r10
aws-nukeAll versions (No fix recorded)
aws-otel-collector-fips< 0.48.0-r2
aws-otel-collector-healthcheck-fipsAll versions (No fix recorded)
aws-signer-notation-plugin-fipsAll versions (No fix recorded)
aws-sigv4-proxy-fipsAll versions (No fix recorded)
azcopyAll versions (No fix recorded)
azure-service-operator-fips< 2.19.0-r3
azure-workload-identity-webhook< 1.5.1-r21
azuredisk-csi-1.32< 1.32.12-r11
azuredisk-csi-fips-1.32< 1.32.12-r12
azuredisk-csi-fips-1.33< 1.33.10-r2
azuredisk-csi-fips-1.34< 1.34.4-r2
azurefile-csi-fips-1.34All versions (No fix recorded) | < 1.34.6-r2
backup-restore-operator-9.0< 9.0.3-r3
backup-restore-operator-fips-10.0< 10.0.4-r2
backup-restore-operator-fips-7.0< 7.0.6-r4
backup-restore-operator-fips-8.1< 8.1.4-r4
backup-restore-operator-fips-9.0< 9.0.3-r3
bank-vaults< 1.33.1-r2
bank-vaults-fips< 1.33.1-r1
bank-vaults-templateAll versions (No fix recorded)
bank-vaults-template-fipsAll versions (No fix recorded)
bento< 1.18.0-r2
blob-csi-1.26< 1.26.12-r2 | All versions (No fix recorded)
blob-csi-fips-1.23< 1.23.11-r76 | All versions (No fix recorded)
blob-csi-fips-1.24< 1.24.11-r23 | All versions (No fix recorded)
blobfuse2-fipsAll versions (No fix recorded)
blobfuse2-fips-health-monitorAll versions (No fix recorded)
boring-registry-fipsAll versions (No fix recorded)
boringssl-fips-static-20240407-toolsAll versions (No fix recorded)
buildahAll versions (No fix recorded)
buildah-fipsAll versions (No fix recorded)
buildctl-fipsAll versions (No fix recorded)
buildkitd-fipsAll versions (No fix recorded)
buildtools-buildifier-fipsAll versions (No fix recorded)
buildtools-buildozer-fipsAll versions (No fix recorded)
cadence-cassandra-toolAll versions (No fix recorded)
cadence-serverAll versions (No fix recorded)
cadence-sql-toolAll versions (No fix recorded)
cadvisor-fipsAll versions (No fix recorded)
calico-goldmane-3.31All versions (No fix recorded) | < 3.31.7-r3
calico-key-cert-provisioner-3.31< 3.31.7-r3
cargobumpAll versions (No fix recorded)
cass-operator< 1.31.0-r1
cass-operator-fips-no-pvc-delete< 1.31.0-r1
ceph-csi-operator< 1.0.1-r1
cephcsi< 3.17.0-r1
cephcsi-fips< 3.17.0-r1
cerbos-fipsAll versions (No fix recorded)
cerbosctl-fipsAll versions (No fix recorded)
cert-exporter< 2.18.0-r10
cert-manager-1.18< 1.18.6-r5
cert-manager-1.19< 1.19.5-r6
cert-manager-1.20< 1.20.2-r8
cert-manager-acmesolver-1.18< 1.18.6-r5
cert-manager-acmesolver-1.19< 1.19.5-r6
cert-manager-acmesolver-fips-1.18< 1.18.6-r2
cert-manager-acmesolver-fips-1.19All versions (No fix recorded)
cert-manager-acmesolver-fips-1.20All versions (No fix recorded)
cert-manager-cainjector-1.18< 1.18.6-r5
cert-manager-cainjector-1.19< 1.19.5-r6
cert-manager-cainjector-1.20< 1.20.2-r8
cert-manager-cainjector-fips-1.18< 1.18.6-r2
cert-manager-cainjector-fips-1.19< 1.19.5-r6
cert-manager-cainjector-fips-1.20< 1.20.2-r5
cert-manager-controller-1.18< 1.18.6-r5
cert-manager-controller-1.19< 1.19.5-r6
cert-manager-controller-1.20< 1.20.2-r8
cert-manager-controller-fips-1.18< 1.18.6-r2
cert-manager-controller-fips-1.19< 1.19.5-r6
cert-manager-controller-fips-1.20< 1.20.2-r5
cert-manager-fips-1.18< 1.18.6-r2
cert-manager-fips-1.19< 1.19.5-r6 | All versions (No fix recorded)
cert-manager-fips-1.20All versions (No fix recorded) | < 1.20.2-r5
cert-manager-google-cas-issuer< 0.11.0-r15
cert-manager-istio-csr-fips< 0.16.0-r12
cert-manager-openshift-routes< 0.9.0-r7
cert-manager-openshift-routes-fips< 0.9.0-r7
cert-manager-startupapicheck-1.18< 1.18.6-r5
cert-manager-startupapicheck-1.19< 1.19.5-r6
cert-manager-startupapicheck-1.20< 1.20.2-r8
cert-manager-startupapicheck-fips-1.18< 1.18.6-r2
cert-manager-startupapicheck-fips-1.19< 1.19.5-r6
cert-manager-startupapicheck-fips-1.20< 1.20.2-r5
cert-manager-webhook-1.18< 1.18.6-r5
cert-manager-webhook-1.19< 1.19.5-r6
cert-manager-webhook-fips-1.18< 1.18.6-r2
cert-manager-webhook-fips-1.19< 1.19.5-r6
cert-manager-webhook-fips-1.20< 1.20.2-r5
cert-manager-webhook-pdns< 2.5.5-r11
certificate-transparency-fips-trillian-ctserverAll versions (No fix recorded)
cgo-pkgbuildAll versions (No fix recorded)
chainguard-partners-demoAll versions (No fix recorded)
chainloop-cli< 1.99.0-r1
chainloop-control-plane< 1.99.0-r1 | All versions (No fix recorded)
chaos-mesh< 2.8.3-r0
chaos-mesh-daemonAll versions (No fix recorded)
chaos-mesh-dashboard< 2.8.3-r0
chaos-mesh-fips< 2.8.2-r11

Show all 199

Alpine1 product

go< 1.26.8-r0

2 vendors · 200 products · Showing 200 of 2750

References

20 links

go.dev/issue/79217ARTICLEREPORT
go.dev/cl/774481ARTICLEFIX
groups.google.com/g/golang-announce/c/tKs3rmcBcKwARTICLEWEB
pkg.go.dev/vuln/GO-2026-5038Advisory
access.redhat.com/errata/RHSA-2026:57456Advisory
access.redhat.com/security/updates/classification/ARTICLE
bugzilla.redhat.com/show_bug.cgi?id=2484204REPORT
security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_57456.jsonAdvisory
access.redhat.com/security/cve/CVE-2026-42504REPORT
www.cve.org/CVERecord?id=CVE-2026-42504AdvisoryREPORT

Show all 20 references