CVE-2026-42556— Postiz stored XSS in public preview page
Get alerts for future matching vulnerabilitiesLog in to subscribe
I. Basic Information for CVE-2026-42556
Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗ Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.
Vulnerability Title
Postiz stored XSS in public preview page
Source: NVD (National Vulnerability Database)
Vulnerability Description
Postiz is an AI social media scheduling tool. From version 2.21.6 to before version 2.21.7, any authenticated user who can create a post can store arbitrary HTML in post content by tampering their own save request and send the public preview link /p/<postId>?share=true to another user. The preview page renders that stored HTML with dangerouslySetInnerHTML on the main application origin. This issue has been patched in version 2.21.7.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L
Source: NVD (National Vulnerability Database)
Vulnerability Type
在Web页面生成时对输入的转义处理不恰当(跨站脚本)
Source: NVD (National Vulnerability Database)
Vulnerability Title
Gitroom Postiz 跨站脚本漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Gitroom Postiz是Gitroom开源的一个社交媒体日程安排工具。 Gitroom Postiz 2.21.6版本至2.21.7之前版本存在跨站脚本漏洞，该漏洞源于任何经过身份验证的用户可通过篡改保存请求在帖子内容中存储任意HTML，预览页面使用dangerouslySetInnerHTML渲染该HTML。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| gitroomhq | postiz-app | >= 2.21.6, < 2.21.7 | - |
II. Public POCs for CVE-2026-42556
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POCPremium
Qwen3.6-35B-A3B · 6482 chars
Paid plan includes:
In-depth vulnerability mechanism
Trigger conditions & impact
Full executable POC code
Exploit chain & mitigation
POC zip download
100+ AI POC generations per month
III. Intelligence Information for CVE-2026-42556
请登录查看更多情报信息。
- Release v2.21.7 · gitroomhq/postiz-app · GitHubx_refsource_MISC
- https://nvd.nist.gov/vuln/detail/CVE-2026-42556
Same Patch Batch · gitroomhq · 2026-05-08 · 3 CVEs total
| CVE-2026-42298 | 10.0 CRITICAL | Postiz: Arbitrary Code Execution and Token Exfiltration in pr-docker-build.yml via untrust |
| CVE-2026-42346 | 6.5 MEDIUM | Postiz: TOCTOU DNS rebinding bypasses all SSRF URL validation paths |
IV. Related Vulnerabilities
Same product: postiz-app
- CVE-2026-42346
Postiz: TOCTOU DNS rebinding bypasses all SSRF URL validatio - CVE-2026-42298
Postiz: Arbitrary Code Execution and Token Exfiltration in p - CVE-2026-40487
Postiz Has Unrestricted File Upload via MIME Type Spoofing t - CVE-2026-40168
Postiz has Server-Side Request Forgery via Redirect Bypass i - CVE-2026-34590
Postiz: SSRF via Webhook Creation Endpoint Missing URL Safet
Same vendor: gitroomhq
- CVE-2026-42346
Postiz: TOCTOU DNS rebinding bypasses all SSRF URL validatio - CVE-2026-42298
Postiz: Arbitrary Code Execution and Token Exfiltration in p - CVE-2026-40487
Postiz Has Unrestricted File Upload via MIME Type Spoofing t - CVE-2026-40168
Postiz has Server-Side Request Forgery via Redirect Bypass i - CVE-2026-34590
Postiz: SSRF via Webhook Creation Endpoint Missing URL Safet
Same weakness: CWE-79
- CVE-2026-8262
Devs Palace ERP Online chart-save cross site scripting - CVE-2026-8256
Devs Palace ERP Online mr-save cross site scripting - CVE-2026-8255
Devs Palace ERP Online add_new_customer cross site scripting - CVE-2026-8254
Devs Palace ERP Online sales_save cross site scripting - CVE-2026-8253
Devs Palace ERP Online purchase_save cross site scripting
V. Comments for CVE-2026-42556
No comments yet