WS Auto-PONG memory exhaustion
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 1 fixed, 2 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-770.
Summary
By default, curl automatically responds to WebSocket PING frames. Because curl lacks an upper bound on memory allocation for unacknowledged frames, a malicious server can exhaust all available memory by flooding curl with rapid, sequential PING messages.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA curl (curl) Fixed in 8.16.1, 8.20.1
Red Hat 2 advisories
- RHSA-2026:34975 Released 2026-07-02 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images cargo-1.96.1-1.hum1@aarch64, cargo-1.96.1-1.hum1@x86_64, clippy-1.96.1-1.hum1@aarch64 +36
- RHSA-2026:29017 Released 2026-06-24 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images curl-8.21.0-0.1.hum1@aarch64, curl-8.21.0-0.1.hum1@src, curl-8.21.0-0.1.hum1@x86_64 +6
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
curl 8.16.1, 8.20.1
2 records Highest priority Priority HIGH 1 HIGH, 1 MEDIUM
Other records, highest priority first
- TI-2026-07845 SASL double-freePriority HIGH 82
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Hardened Images | Fixed | RHSA-2026:29017, RHSA-2026:34975 |
Not affected: 7 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Container Platform 5
- Red Hat OpenShift Dev Spaces
- Red Hat Trusted Profile Analyzer
Timeline
- 2026-10-02 Threatist record created from CVE-2026-11586
- 2026-10-03 Alias added: GHSA-c68q-h477-5646
- 2026-10-25 EPSS moved to the 50th–90th percentile
- 2026-11-05 Affected versions changed · Red Hat
References
More curl vulnerabilities
- TI-2023-19922 Out-of-bounds write in curl CVSS 3.1CRITICAL 9.8
- TI-2026-16162 Negotiate ambient user conn reuse CVSS 3.1CRITICAL 9.8
- TI-2026-10231 cross-origin Digest auth state leak CVSS 3.1CRITICAL 9.8
- TI-2026-09063 HTTP/2 stream-dependency tree UAF CVSS 3.1CRITICAL 9.8
- TI-2026-07976 stale proxy password leak CVSS 3.1CRITICAL 9.8
- TI-2026-07845 SASL double-free CVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-11586 · CVE Program
- CVE-2026-11586 · NVD
- FIRST EPSS
- GHSA-c68q-h477-5646 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-11586 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences