Description
Ruby JSON is a JSON implementation for Ruby. Versions 2.9.0 through 2.19.8 are vulnerable to heap buffer overflow when the JSON generator is provided with an oversized streamed object. When streaming to an IO JSON.dump(obj, io) and JSON::State#generate(obj, io) can write past the internal JSON generator buffer when a streamed object contains an
attacker-controlled string near 16 KB. Exploitation would result in a reliable process crash/denial of service. This issue has been fixed in version 2.19.9.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| ruby | json | >= 2.9.0, < 2.19.9 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | ruby-json | 2.19.9+dfsg-1 | — |
| Debian 13 | ruby-json | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | jruby +2 | No fix yet | — |
| Ubuntu 26.04 LTS | jruby +2 | No fix yet | — |
| Ubuntu 25.10 | jruby +2 | No fix yet | — |
| Ubuntu 24.04 LTS | jruby +2 | No fix yet | — |
| Ubuntu 22.04 LTS | ruby3.0 +1 | No fix yet | — |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | jruby +1 | No fix yet | — |
| Ubuntu 18.04 LTS | jruby +1 | No fix yet | — |
| Ubuntu 16.04 LTS | jruby +1 | No fix yet | — |
| Ubuntu 14.04 LTS | ruby-json | No fix yet | — |
| Ubuntu Pro 20.04 LTS | ruby2.7 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | ruby2.5 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | ruby2.3 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | jruby | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | ruby3.4 +5 | 3.4.10-31.5.hum1 | RHSA-2026:48482 |
| Red Hat Hardened Images 1 | ruby4.0 +5 | 4.0.6-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-bigdecimal | 4.0.1-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-devel +2 | 4.0.16-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-io-console | 0.8.2-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-irb | 1.16.0-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-json | 2.18.0-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-minitest | 6.0.0-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-power_assert | 3.0.1-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-psych | 5.3.1-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-racc | 1.8.1-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-rake | 13.3.1-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-rbs | 3.10.0-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-rdoc | 7.0.4-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-rexml | 3.4.4-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-rss | 0.3.2-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-test-unit | 3.7.5-37.1.hum1 | RHSA-2026:47932 |
| Red Hat Hardened Images 1 | rubygem4.0-typeprof | 0.31.1-37.1.hum1 | RHSA-2026:47932 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | cinc-auditor | 7.1.7-r7 | — |
| Wolfi rolling | ruby-3.4 | No fix yet | — |
| Wolfi rolling | ruby3.2-fluentd-kubernetes-daemonset-1.19-kinesis | 1.19.2.1.1-r6 | — |
| Wolfi rolling | ruby3.2-kube-logging-operator-fluentd-outputs +1 | 6.7.0-r8 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| RubyGems | json | >= 2.9.0, < 2.19.9 | 2.19.9 | GHSA-x2f5-4prf-w687 |
Advisories 2
- RHSA-2026:48482 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Oct 6, 2026
- RHSA-2026:47932 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Oct 6, 2026