Medium severity · published Sep 14, 2026
CVE-2026-54247
Skipper: Unbounded Request Body Read in Admission Webhook Causes Memory Exhaustion DoS
4.3
CVSS
0.3%
EPSS
No
On KEV
Description
Skipper is an HTTP router and reverse proxy for service composition. Prior to 0.26.22, Handler in dataclients/kubernetes/admission/admission.go passes the body of requests to the Kubernetes admission endpoint at :9443/admission directly to io.ReadAll(r.Body) without a size limit. An attacker with in-cluster network access and a valid Kubernetes client certificate can send a very large body that causes unbounded memory allocation and an out-of-memory termination of the Skipper process. The disruption is limited to Ingress and RouteGroup admission rather than pod creation or unrelated admission controllers, and Kubernetes normally restarts the process. This issue is fixed in version 0.26.22.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 22% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SK
skipper · zalando
< 0.26.22 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-54247
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-54247
github.com
https://github.com/zalando/skipper/commit/c3d156c6caaefecc9a46774c0f9c3c70b97160b4
github.com
https://github.com/zalando/skipper/pull/4053
github.com
https://github.com/zalando/skipper/releases/tag/v0.26.22
github.com
https://github.com/zalando/skipper/security/advisories/GHSA-cwxq-rc9x-2jvv
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