Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Affected versions of the http4k-core Maven package (org.http4k:http4k-core) can be exhausted of memory by a small gzip-encoded request body that expands to gigabytes, because the GZip and GunZip filters impose no decompressed-size limit. Any unauthenticated client that can send requests to an affected server can cause a denial of service. Upgrade to 6.49.0.0 or 5.42.0.0; for the 4.x line, the advisory lists 4.51.0.0 as the fix, which is available through enterprise support.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 7.5 | High | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0063, the 50th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:19 UTC First seen by agentprime
- 31 Oct 2026, 14:19 UTC Confirmed by OSV