VulnerabilityAnalyzed
CVE-2026-11586
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.
HIGH 7.5EPSS 0.61%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.61%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.61% probability · 47th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-770
- Affected
- haxx/curl
- Source
- 2499f714-1537-4658-8207-48ae4bb9eae9
References
- https://curl.se/docs/CVE-2026-11586.htmlPatch, Vendor Advisory
- https://curl.se/docs/CVE-2026-11586.jsonVendor Advisory
- https://hackerone.com/reports/3788931Exploit, Issue Tracking, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.