CVE-2021-33570

Name: CVE-2021-33570
Creator: NVD / NIST
Published: 2021-05-25T22:15:10.353+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 3.56%

Last modified Jun 17, 2026

CVE-2021-33570 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. 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.. EPSS estimates a 3.56% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

5.4/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

3.56%

87.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Postbird Project	Postbird	0.8.4

References

http://packetstormsecurity.com/files/162831/Postbird-0.8.4-Cross-Site-Scripting-Local-File-Inclusion.htmlExploit, Third Party Advisory, VDB Entry
http://packetstormsecurity.com/files/162872/Postbird-0.8.4-XSS-LFI-Insecure-Data-Storage.htmlThird Party Advisory, VDB Entry
https://github.com/Paxa/postbird/issues/132Issue Tracking, Third Party Advisory
https://github.com/Paxa/postbird/issues/133Issue Tracking, Third Party Advisory
https://github.com/Paxa/postbird/issues/134Issue Tracking, Third Party Advisory
https://github.com/Tridentsec-io/postbirdExploit, Third Party Advisory
https://tridentsec.io/blogs/postbird-cve-2021-33570/Broken Link, Third Party Advisory, URL Repurposed
https://www.exploit-db.com/exploits/49910Exploit, Third Party Advisory, VDB Entry
http://packetstormsecurity.com/files/162831/Postbird-0.8.4-Cross-Site-Scripting-Local-File-Inclusion.htmlExploit, Third Party Advisory, VDB Entry
http://packetstormsecurity.com/files/162872/Postbird-0.8.4-XSS-LFI-Insecure-Data-Storage.htmlThird Party Advisory, VDB Entry
https://github.com/Paxa/postbird/issues/132Issue Tracking, Third Party Advisory
https://github.com/Paxa/postbird/issues/133Issue Tracking, Third Party Advisory
https://github.com/Paxa/postbird/issues/134Issue Tracking, Third Party Advisory
https://github.com/Tridentsec-io/postbirdExploit, Third Party Advisory
https://tridentsec.io/blogs/postbird-cve-2021-33570/Broken Link, Third Party Advisory, URL Repurposed
https://www.exploit-db.com/exploits/49910Exploit, Third Party Advisory, VDB Entry

Timeline

Published: May 25, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-33570?

How severe is CVE-2021-33570?

CVE-2021-33570 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 3.56% probability of exploitation in the next 30 days.

How do I fix CVE-2021-33570?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-33570?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST