CVE-2023-28103 | Prototype pollution in matrix-react-sdk

matrix-react-sdk is a Matrix chat protocol SDK for React Javascript. In certain configurations, data sent by remote servers containing special strings in key locations could cause modifications of the `Object.prototype`, disrupting matrix-react-sdk functionality, causing denial of service and potentially affecting program logic. This is fixed in matrix-react-sdk 3.69.0 and users are advised to upgrade. There are no known workarounds for this vulnerability. Note this advisory is distinct from GHSA-2x9c-qwgf-94xr which refers to a similar issue.

Published: 2023-03-28 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-28103 is rated Moderate Risk (49.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.71%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-28103

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.76% 0.71% -0.05%
2 2026-05-26 0.60% 0.76% +0.16%
3 2026-03-30 — 0.60% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-28103

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 4.2 [email protected]
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 4.2 [email protected]

Weakness enumeration for CVE-2023-28103

GitHub Security Advisory for CVE-2023-28103

GHSA-6g43-88cp-w5gv · Severity: high · Ecosystem: npm — Prototype pollution in matrix-react-sdk

OS Trackers for CVE-2023-28103

vendor priority summary link
alpine high CVE-2023-28103: 2 source package rows (element-web, riot-web); 8 state rows across 7 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community); fixed 8, open 0. https://security.alpinelinux.org/vuln/CVE-2023-28103

Affected software / configurations for CVE-2023-28103

Vendor Product Version Raw CPE
matrix-react-sdk_project matrix-react-sdk < 3.69.0 cpe:2.3:a:matrix-react-sdk_project:matrix-react-sdk:*:*:*:*:*:node.js:*:*

References for CVE-2023-28103

cvelogic Threat Intelligence