Heap exhaustion via unbounded simple string or bulk string allocation in Vert.x Redis client

published 2026-11-03 5 d ago modified 2026-11-03 5 d ago also EUVD-2026-115881

cvss: 5.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits: 0; none known

In Eclipse Vert.x versions [4.0.0, 4.5.35] or [5.0.0, 5.2.2], when a malicious server keeps sending bytes on an EOL-terminated line (not length-prefixed, for example a simple string [1]), we'll keep growing the buffer without bounds, eventually leading to an OOM. We need to have a configurable limit for EOL-terminated lines.

If a malicious server sends a specially crafted RESP response (for example a bulk string [2] with missing CRLF trailer), the parser enters an infinite loop where it keeps parsing the same buffer and pushing the same response to the caller, which may lead e.g. to an OOM if the consumer just buffers the responses. We must fix the parser to avoid this infinite looping.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-118488 updated 2026-11-07 cvss 5.9

io.vertx/vertx-redis-client: vertx-redis-client: Denial of Service via malformed server responses

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 5 d ago (2026-11-03)

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/vert-x3/vertx-redis-client/security/advisories/GHSA-7f58-g87w-gx7p referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Eclipse Foundation Eclipse Vert.x

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

CVE List CVE-2026-118488
NVD CVE-2026-118488

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