CVE-2021-33570

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-05-25 · updated 2026-06-17
Weakness: CWE-79

Description

Postbird 0.8.4 allows stored XSS via the onerror attribute of an IMG element in any PostgreSQL database table. This can result in reading local files via vectors involving XMLHttpRequest and open of a file:/// URL, or discovering PostgreSQL passwords via vectors involving Window.localStorage and savedConnections.

Affected products

Postbird Project Postbird: 0.8.4

References

http://packetstormsecurity.com/files/162831/Postbird-0.8.4-Cross-Site-Scripting-Local-File-Inclusion.html
http://packetstormsecurity.com/files/162872/Postbird-0.8.4-XSS-LFI-Insecure-Data-Storage.html
https://github.com/Paxa/postbird/issues/132
https://github.com/Paxa/postbird/issues/133
https://github.com/Paxa/postbird/issues/134
https://github.com/Tridentsec-io/postbird
https://tridentsec.io/blogs/postbird-cve-2021-33570/
https://www.exploit-db.com/exploits/49910
http://packetstormsecurity.com/files/162831/Postbird-0.8.4-Cross-Site-Scripting-Local-File-Inclusion.html
http://packetstormsecurity.com/files/162872/Postbird-0.8.4-XSS-LFI-Insecure-Data-Storage.html
https://github.com/Paxa/postbird/issues/132
https://github.com/Paxa/postbird/issues/133

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