From 19.0.0 until 19.0.9, 19.1.10, 19.2.9, and 19.3.1, the react-server-dom-webpack, react-server-dom-parcel, and
Affects reactSource GCVE Database
Not known to be exploited · CVSS 9.5 Critical · fixed in 19.0.9 : patch react as a priority.
Data as of 13 Nov 2026, 22:22 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 4.0 | 9.5 |
|---|
- Patch
- Available – fixed in 19.0.9
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10reactpkg:deb/ubuntu/react?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSreactpkg:deb/ubuntu/react?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSreactpkg:deb/ubuntu/react?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSreactpkg:deb/ubuntu/react?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSreactpkg:deb/ubuntu/react?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu 18.04 LTSreactpkg:deb/ubuntu/react?arch=source&distro=bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade to React versions 19.0.9, 19.1.10, 19.2.9, or 19.3.1 or later, where this vulnerability is fixed. Applications not using React Server Components or server-side React are not affected and do not require action.
Description
React versions from 19.0.0 up to but not including 19.0.9, 19.1.10, 19.2.9, and 19.3.1 have a vulnerability in the react-server-dom-webpack, react-server-dom-parcel, and react-server-dom-turbopack packages. This vulnerability allows unauthenticated remote code execution via crafted payloads targeting frameworks that support React Server Components. The issue affects rare cases involving responses transporting multiple typed arrays and attacker-controlled values. Applications not using React Server Components or server-side React are not affected. The vulnerability is fixed in versions 19.0.9, 19.1.10, 19.2.9, and 19.3.1.
References
- ubuntu.com/security/CVE-2026-126187 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-126187 (opens in a new tab)
- github.com/react/react/commit/0c9913ae87283f96e868a8f1c20a3389827632d0 (opens in a new tab)
- github.com/react/react/commit/249ac87b0dadea4ba024d1393e5cb60cf1186080 (opens in a new tab)
- github.com/react/react/commit/3d06b4005ac0cf9dec37267f26174adfe6d83611 (opens in a new tab)
- github.com/react/react/commit/611d9217df39cf7b8ac91b2e41fd00555923e904 (opens in a new tab)
- github.com/react/react/commit/61aa00df822d0eb76d0362eb8b6fdd3527693efe (opens in a new tab)
- github.com/react/react/pull/37842 (opens in a new tab)
- github.com/react/react/pull/37843 (opens in a new tab)
- github.com/react/react/pull/37844 (opens in a new tab)
- github.com/react/react/pull/37845 (opens in a new tab)
- github.com/react/react/pull/37846 (opens in a new tab)
- github.com/react/react/releases/tag/v19.0.9 (opens in a new tab)
- github.com/react/react/releases/tag/v19.1.10 (opens in a new tab)
- github.com/react/react/releases/tag/v19.2.9 (opens in a new tab)
- github.com/react/react/releases/tag/v19.3.1 (opens in a new tab)
- github.com/react/react/security/advisories/GHSA-xqc2-xf4c-x3h3 (opens in a new tab)