CVE-2026-39835
Vulnerability Summary
Timeline
Description
SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.
CVSS Metrics
- v3.1•MEDIUM•Score: 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- v3.1•HIGH•Score: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Trends
Current EPSS score: 0.50%• Percentile: 42%
Techniques & Countermeasures
- CWE-295•Improper Certificate Validation
The product does not validate, or incorrectly validates, a certificate.
- CWE-476•NULL Pointer Dereference
The product dereferences a pointer that it expects to be valid but is NULL.
Affected Systems
- chainguard•aactl
< 0.4.12-r53
- chainguard•act
< 0.2.88-r6
- chainguard•actions-runner-controller
< 0
- chainguard•actions-runner-controller-fips
< 0
- chainguard•age
< 0
- chainguard•age-fips
< 0 | < 1.3.1-r11
- chainguard•agentbeat
< 0
- chainguard•agentbeat-fips
< 0
- chainguard•amass
< 0
- chainguard•amazon-cloudwatch-agent
< 0
- chainguard•amazon-cloudwatch-agent-fips
< 0
- chainguard•amazon-cloudwatch-agent-operator
< 0
- chainguard•amazon-cloudwatch-agent-operator-fips
< 0
- chainguard•amazon-ssm-agent
< 3.3.4515.0-r2
- chainguard•amazon-ssm-agent-ecs-exec
< 3.3.4515.0-r2
- chainguard•amazon-ssm-agent-ecs-exec-fips
< 3.3.4515.0-r3
- chainguard•amazon-ssm-agent-fips
< 3.3.4515.0-r3
- chainguard•apache-exporter
< 0
- chainguard•apko
< 1.2.14-r2
- chainguard•apko-fips
< 1.2.14-r2
- chainguard•apm-server-8.19
< 0
- chainguard•apm-server-9.1
all
- chainguard•apm-server-9.3
< 0
- chainguard•apm-server-9.4
< 0
- chainguard•apply-cve-bump
< 0.2.280-r0
- chainguard•argo-cd-3.0
all
- chainguard•argo-cd-3.0-compat
all
- chainguard•argo-cd-3.1
< 3.1.16-r3
- chainguard•argo-cd-3.1-compat
< 3.1.16-r3
- chainguard•argo-cd-3.3-compat
< 3.3.14-r9
- chainguard•argo-cd-3.4
< 3.4.2-r4
- chainguard•argo-cd-3.4-compat
< 3.4.2-r4
- chainguard•argo-cd-fips-3.0
all
- chainguard•argo-cd-fips-3.0-compat
all
- chainguard•argo-cd-fips-3.1
< 3.1.16-r1
- chainguard•argo-cd-fips-3.1-compat
< 3.1.16-r1
- chainguard•argo-cd-fips-3.2
< 3.2.12-r5
- chainguard•argo-cd-fips-3.2-compat
< 3.2.12-r5
- chainguard•argo-cd-fips-3.4
< 3.4.2-r4
- chainguard•argo-cd-fips-3.4-compat
< 3.4.2-r4
- chainguard•argo-events
< 1.9.10-r24
- chainguard•argo-events-fips
< 1.9.10-r17
- chainguard•argo-rollouts
< 0
- chainguard•argo-workflow-controller-3.6
< 3.6.19-r7
- chainguard•argo-workflow-controller-fips-3.6
< 3.6.19-r9
- chainguard•argo-workflow-executor-3.6
< 3.6.19-r7
- chainguard•argo-workflow-executor-fips-3.6
< 3.6.19-r9
- chainguard•argo-workflows-3.6
< 3.6.19-r7
- chainguard•argo-workflows-fips-3.6
< 3.6.19-r9
- chainguard•argocd-image-updater
< 1.2.1-r2
Showing first 50 affected entries in server-rendered view.
References (66)
- https://go.dev/issue/79563
- https://groups.google.com/g/golang-announce/c/a082jnz-LvI
- https://go.dev/cl/781660
- https://pkg.go.dev/vuln/GO-2026-5015
- https://nvd.nist.gov/vuln/detail/CVE-2026-39835
- https://cs.opensource.google/go/x/crypto
- https://access.redhat.com/security/cve/CVE-2026-39835
- https://bugzilla.redhat.com/show_bug.cgi?id=2480680
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39835.json
- https://access.redhat.com/errata/RHSA-2026:36199
- https://access.redhat.com/errata/RHSA-2026:26547
- https://access.redhat.com/errata/RHSA-2026:36625
- https://access.redhat.com/errata/RHSA-2026:36207
- https://access.redhat.com/errata/RHSA-2026:26546
- https://access.redhat.com/errata/RHSA-2026:36319
- https://access.redhat.com/errata/RHSA-2026:36648
- https://access.redhat.com/errata/RHSA-2026:36796
- https://access.redhat.com/errata/RHSA-2026:37072
- https://access.redhat.com/errata/RHSA-2026:37123
- https://access.redhat.com/errata/RHSA-2026:36651
- https://access.redhat.com/errata/RHSA-2026:36797
- https://access.redhat.com/errata/RHSA-2026:37271
- https://access.redhat.com/errata/RHSA-2026:37268
- https://access.redhat.com/errata/RHSA-2026:37410
- https://access.redhat.com/errata/RHSA-2026:37387
- https://access.redhat.com/errata/RHSA-2026:37272
- https://access.redhat.com/errata/RHSA-2026:37286
- https://access.redhat.com/errata/RHSA-2026:37296
- https://access.redhat.com/errata/RHSA-2026:38504
- https://access.redhat.com/errata/RHSA-2026:41019
- https://access.redhat.com/errata/RHSA-2026:40945
- https://access.redhat.com/errata/RHSA-2026:40118
- https://access.redhat.com/errata/RHSA-2026:41036
- https://access.redhat.com/errata/RHSA-2026:41031
- https://access.redhat.com/errata/RHSA-2026:41066
- https://access.redhat.com/errata/RHSA-2026:40262
- https://access.redhat.com/errata/RHSA-2026:40972
- https://access.redhat.com/errata/RHSA-2026:40974
- https://access.redhat.com/errata/RHSA-2026:40969
- https://access.redhat.com/errata/RHSA-2026:42146
- https://access.redhat.com/errata/RHSA-2026:42796
- https://access.redhat.com/errata/RHSA-2026:51036
- https://access.redhat.com/errata/RHSA-2026:48151
- https://access.redhat.com/errata/RHSA-2026:51033
- https://access.redhat.com/errata/RHSA-2026:43692
- https://access.redhat.com/errata/RHSA-2026:51038
- https://access.redhat.com/errata/RHSA-2026:52857
- https://access.redhat.com/errata/RHSA-2026:52910
- https://access.redhat.com/errata/RHSA-2026:43052
- https://access.redhat.com/errata/RHSA-2026:46885
- https://access.redhat.com/errata/RHSA-2026:47949
- https://access.redhat.com/errata/RHSA-2026:47735
- https://access.redhat.com/errata/RHSA-2026:54525
- https://security-tracker.debian.org/tracker/CVE-2026-39835
- https://access.redhat.com/errata/RHSA-2026:57194
- https://ubuntu.com/security/CVE-2026-39835
- https://www.cve.org/CVERecord?id=CVE-2026-39835
- https://access.redhat.com/errata/RHSA-2026:59467
- https://access.redhat.com/errata/RHSA-2026:59593
- https://access.redhat.com/errata/RHSA-2026:60520
- https://access.redhat.com/errata/RHSA-2026:62260
- https://pkg.go.dev
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39835.json
- https://access.redhat.com/errata/RHSA-2026:65126
- https://access.redhat.com/errata/RHSA-2026:66521
- https://access.redhat.com/errata/RHSA-2026:66022