Spin has memory leaks in various WIT interfaces

published 2026-02-26 8 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-8796

cvss: 6.9; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 18%
public exploits: 0; none known

Spin is an open source developer tool for building and running serverless applications powered by WebAssembly. When Spin is configured to allow connections to a database or web server which could return responses of unbounded size (e.g. tables with many rows or large content bodies), Spin may in some cases attempt to buffer the entire response before delivering it to the guest, which can lead to the host process running out of memory, panicking, and crashing. In addition, a malicious guest application could incrementally insert a large number of rows or values into a database and then retrieve them all in a single query, leading to large host allocations. Spin 3.6.1, SpinKube 0.6.2, and `containerd-shim-spin` 0.22.1 have been patched to address the issue. As a workaround, configure Spin to only allow access to trusted databases and HTTP servers which limit response sizes.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 8 mo ago (2026-02-26)

Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	6.9	CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H
CNA	4.0	6.9	CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/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:X/R:X/V:X/RE:X/U:X

Affected products

spinframework spin
spinframework SpinKube
spinframework containerd-shim-spin

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling
CWE-774 Allocation of File Descriptors or Handles Without Limits or Throttling
CWE-789 Memory Allocation with Excessive Size Value

References

github.com /spinframework/spin/security/advisories/GHSA-mv4f-6ffm-32wx

Sources

CVE List CVE-2026-27887
NVD CVE-2026-27887

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary