GHSA-JPPX-W49H-X2QQ
Vulnerability from github – Published: 2026-07-22 21:32 – Updated: 2026-07-22 21:32The SpdyHttpDecoder handler in Netty's SPDY-to-HTTP codec allocates a pooled ByteBuf when processing a client-initiated SYN_STREAM frame with FLAG_FIN=0, storing the partially-constructed FullHttpRequest in an internal map (messageMap) to accumulate subsequent DATA frames. When the remote peer sends an RST_STREAM for that stream, or when the accumulated content exceeds maxContentLength, the decoder removes the entry from the map but never releases the pooled ByteBuf, permanently leaking the allocated memory.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 4.2.15.Final"
},
"package": {
"ecosystem": "Maven",
"name": "io.netty:netty-codec-http"
},
"ranges": [
{
"events": [
{
"introduced": "4.2.0.Final"
},
{
"fixed": "4.2.16.Final"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 4.1.135.Final"
},
"package": {
"ecosystem": "Maven",
"name": "io.netty:netty-codec-http"
},
"ranges": [
{
"events": [
{
"introduced": "4.1.0.Final"
},
{
"fixed": "4.1.136.Final"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-56745"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": true,
"github_reviewed_at": "2026-07-22T21:32:24Z",
"nvd_published_at": "2026-07-21T22:17:14Z",
"severity": "HIGH"
},
"details": "The `SpdyHttpDecoder` handler in Netty\u0027s SPDY-to-HTTP codec allocates a pooled `ByteBuf` when processing a client-initiated `SYN_STREAM` frame with `FLAG_FIN=0`, storing the partially-constructed `FullHttpRequest` in an internal map (`messageMap`) to accumulate subsequent `DATA` frames. When the remote peer sends an `RST_STREAM` for that stream, or when the accumulated content exceeds `maxContentLength`, the decoder removes the entry from the map but **never releases the pooled ByteBuf**, permanently leaking the allocated memory.",
"id": "GHSA-jppx-w49h-x2qq",
"modified": "2026-07-22T21:32:24Z",
"published": "2026-07-22T21:32:24Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/netty/netty/security/advisories/GHSA-jppx-w49h-x2qq"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56745"
},
{
"type": "WEB",
"url": "https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b"
},
{
"type": "WEB",
"url": "https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6"
},
{
"type": "PACKAGE",
"url": "https://github.com/netty/netty"
},
{
"type": "WEB",
"url": "https://github.com/netty/netty/releases/tag/netty-4.1.136.Final"
},
{
"type": "WEB",
"url": "https://github.com/netty/netty/releases/tag/netty-4.2.16.Final"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Netty: [SpdyHttpDecoder] ByteBuf Reference Leak on RST_STREAM Leads to Native Memory Exhaustion"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.