CVE-2026-93894
Summary
| CVE | CVE-2026-93894 |
|---|---|
| State | PUBLISHED |
| Assigner | mitre |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-18 21:18:49 UTC |
| Updated | 2026-09-22 20:00:03 UTC |
| Description | In Vinyl Cache before 9.0,2, workspace buffer overflow vulnerability was found in the .upper() and .lower() string type methods of VCL. This can be used as a remote denial of service (DoS) vector to make the child process segfault or assert, and then restart. Effectively exploiting this vulnerability requires prior knowledge about the VCL in use and the ability to craft a request that contains a string that is long enough to fill the remaining workspace at the call site while staying under the different request size limits (http_req_size, http_req_hdr_len, etc.). |
Risk And Classification
Primary CVSS: v4.0 2.3 LOW from [email protected]
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:N/R:A/V:D/RE:L/U:Clear
EPSS: 0.002500000 probability, percentile 0.167130000 (date 2026-09-22)
Problem Types: CWE-787 | CWE-787 CWE-787 Out-of-bounds Write
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 2.3 | LOW | CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 2.3 | LOW | CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/AU:N/... |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
HighAttack Requirements
PresentPrivileges Required
LowUser Interaction
NoneConfidentiality
NoneIntegrity
NoneAvailability
LowSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:N/R:A/V:D/RE:L/U:Clear
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Vinyl-Cache | Vinyl Cache | affected 9.0.2 semver | Not specified |
| CNA | Vinyl-Cache | Vinyl Cache | affected 90f5bacc14b2404e6cc349ba015f0f73b8515136 git | Not specified |
| CNA | Varnish-Software | Varnish Cache | affected 9.0.0 9.0.4 semver | Not specified |
| CNA | Varnish-Software | Varnish Cache | affected c5078ae575201b05ae8674a90ddb19ffe7f4b439 git | Not specified |
| CNA | Varnish-Software | Varnish Cache | affected 6.3.0 8.0.2 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| vinyl-cache.org/security/VSV00020.html | [email protected] | vinyl-cache.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
Solutions
CNA: Update to unaffected Version
Workarounds
CNA: replace the .upper() and .lower() VCL type method calls by their respective vmod_std counterparts: std.toupper() and std.tolower().
There are currently no legacy QID mappings associated with this CVE.