CVE-2021-43099

Public Exploit

Description

An Archive Extraction (AKA "Zip Slip) vulnerability exists in bbs 5.3 in the UpgradeNow function in UpgradeManageAction.java, which unzips the arbitrary upladed zip file without checking filenames. The vulnerability is exploited using a specially crafted archive that holds directory traversal filenames (e.g. ../../evil.exe).

Category

4.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.92% Top 30%
Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/diyhi/bbs/issues/51 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-43099?
CVE-2021-43099 has been scored as a medium severity vulnerability.
How to fix CVE-2021-43099?
To fix CVE-2021-43099, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43099 being actively exploited in the wild?
It is possible that CVE-2021-43099 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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