CVE search · CVE-2026-40394
CVE-2026-40394
high 7.5
Varnish Cache 9 before 9.0.1 and Varnish Enterprise before 6.0.16r11 allows a "workspace overflow" denial of service (daemon panic) for certain amounts of prefetched data. The setup of an HTTP/2 session starts with a speculative HTTP/1 transport, and upon upgrading to h2 the HTTP/1 request is repurposed as stream zero. During the upgrade, a buffer allocation is made to reserve space to send frames to the client. This allocation would split the original workspace, and depending on the amount of prefetched data, the next fetch could perform a pipelining operation that would run out of workspace.
Details
- Status
- Analyzed
- Published
- Last changed
- Source
- cve@mitre.org
- Weakness
- CWE-670
Severity
| Version | Score | Vector | Source |
|---|---|---|---|
| CVSS 3.1 | medium 4.0 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L |
cve@mitre.orgSecondary |
| CVSS 3.1 | high 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
nvd@nist.govPrimary |
Affected products
Vendor and product from the NVD’s CPE applicability statements. Versions and conditions are on the NVD’s page.
- varnish-software · varnish_enterprise
- vinyl-cache · vinyl_cache
References
- https://docs.varnish-software.com/security/VEV00002/Vendor Advisory