Apache Tomcat: Stale HPACK emitter injects trailers into recycled pooled Request
Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in Apache Tomcat allows an attacker to inject trailer fields into another HTTP/2 request. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.39 through 9.0.121. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.59 through 8.5.100. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60, 9.0.122, which fix the issue.
CVE-2026-77762
Primary source · Revision 2
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-77762
Apache Tomcat
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "Apache Software Foundation",
"product": "Apache Tomcat",
"versions": [
{
"status": "affected",
"version": "11.0.0-M1",
"versionType": "semver",
"lessThanOrEqual": "11.0.25"
},
{
"status": "affected",
"version": "10.1.0-M1",
"versionType": "semver",
"lessThanOrEqual": "10.1.59"
},
{
"status": "affected",
"version": "9.0.39",
"versionType": "semver",
"lessThanOrEqual": "9.0.121"
},
{
"status": "affected",
"version": "8.5.59",
"versionType": "semver",
"lessThanOrEqual": "8.5.100"
},
{
"status": "unaffected",
"version": "0",
"versionType": "semver",
"lessThanOrEqual": "7.0.109"
}
],
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-77762
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #59547 · Revision 2
- Added to Heist Feed
- Publisher date