Cross-Site Scripting vulnerability in @backstage/plugin-auth-backend

TRUNG BÌNH 6.1CVE-2021-43776 · GHSA-w7fj-336r-vw49 · Công bố 26/11/2021 · cập nhật 17/06/2026

Tóm tắt nhanh

CVE-2021-43776 là lỗ hổng mức TRUNG BÌNH (CVSS 6.1) ảnh hưởng auth backend (linuxfoundation), @backstage/plugin-auth-backend.
Xác suất bị khai thác trong 30 ngày tới (EPSS): 0.68%, cao hơn 52.3% các lỗ hổng khác.
Cách xử lý: cập nhật lên 0.4.9 hoặc mới hơn.

Gói / sản phẩm	Phiên bản bị ảnh hưởng	Phiên bản đã vá
auth backend linuxfoundation	`< 0.4.9`	`0.4.9`
@backstage/plugin-auth-backend npm	`< 0.4.9`	`0.4.9`

Mô tả

Impact

This vulnerability allows a malicious actor to trick another user into visiting a vulnerable URL that executes an XSS attack. This attack can potentially allow the attacker to exfiltrate access tokens or other secrets from the user's browser. The default CSP does prevent this attack, but it is expected that some deployments have these policies disabled due to incompatibilities.

Patches

This is vulnerability is patched in version 0.4.9 of @backstage/plugin-auth-backend.

For more information

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Mô tả của NVD

Backstage is an open platform for building developer portals. In affected versions the auth-backend plugin allows a malicious actor to trick another user into visiting a vulnerable URL that executes an XSS attack. This attack can potentially allow the attacker to exfiltrate access tokens or other secrets from the user's browser. The default CSP does prevent this attack, but it is expected that some deployments have these policies disabled due to incompatibilities. This is vulnerability is patched in version `0.4.9` of `@backstage/plugin-auth-backend`.