CVE-2026-44893
HIGH 7.5Netty is a network application framework for development of protocol servers and clients. In netty-codec-haproxy prior to versions 4.1.135.Final and 4.2.15.Final, when decoding a PP2_TYPE_SSL TLV, HAProxyMessage.readNextTLV() first calls `header.retainedSlice(header.readerIndex(), length)` and only then reads the 1-byte client field and 4-byte verify field. If the attacker sets the TLV length below 5, the subsequent readByte/readInt throws IndexOutOfBoundsException. HAProxyMessageDecoder only catches HAProxyProtocolException around this call, so the IOOBE propagates and the retained slice on the pooled cumulation buffer is never released. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
Severe if exploited (CVSS 7.5), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.6%chance of exploitation in 30 days · 45th percentile
Impact if exploited
7.5CVSS 3.1 · HIGH
- ConfidentialityNone
- IntegrityNone
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-44893/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-44893/poc.json
Affected
Products Netty Red Hat Build Of Apache Camel 3.33 For Quarkus 3.33.2.Sp1 Red Hat Build Of Apache Camel 4.18.1.P1 For Spring Boot 3.5.16 Red Hat Build Of Quarkus 3.27.4.Sp1 Red Hat Build Of Quarkus 3.33.2.Sp1 Red Hat Data Grid 8.6.2 Streams For Apache Kafka 2.9.4 Red Hat Openshift Dev Spaces 3.29 Cryostat 4 Openshift Serverless Red Hat Amq Broker 7 Red Hat Build Of Apache Camel 4 For Quarkus 3
Weakness (CWE)
- CWE-703: : Improper Check or Handling of Exceptional Conditions
- CWE-805: Buffer Access with Incorrect Length Value
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| Netty | Netty | < 4.1.135 |
| Netty | Netty | ≥ 4.2.0 and < 4.2.15 |
All CVSS metrics
- HIGH 7.5 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - HIGH 7.5 v3.1 · ADP Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - HIGH 7.5 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
Advisories
- https://github.com/netty/netty/security/advisories/GHSA-cc37-9q2j-3hfv
- https://access.redhat.com/errata/RHSA-2026:26586
- https://access.redhat.com/errata/RHSA-2026:41951
- https://access.redhat.com/errata/RHSA-2026:36820
- https://access.redhat.com/errata/RHSA-2026:37390
- https://access.redhat.com/errata/RHSA-2026:26018
- https://access.redhat.com/errata/RHSA-2026:26017
- https://access.redhat.com/errata/RHSA-2026:34608
Technical & other
- https://github.com/netty/netty/releases/tag/netty-4.1.135.Final
- https://github.com/netty/netty/releases/tag/netty-4.2.15.Final
- https://access.redhat.com/security/cve/CVE-2026-44893
- https://bugzilla.redhat.com/show_bug.cgi?id=2488383
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44893.json