CVE-2023-4255

Public Exploit
W3m: out-of-bounds write in function checktype() in etc.c (incomplete fix for cve-2022-38223)

Description

An out-of-bounds write issue has been discovered in the backspace handling of the checkType() function in etc.c within the W3M application. This vulnerability is triggered by supplying a specially crafted HTML file to the w3m binary. Exploitation of this flaw could lead to application crashes, resulting in a denial of service condition.

Category

5.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.02%
Third-Party Advisory redhat.com
Affected: n/a w3m
Affected: Fedora Fedora
Affected: Fedora Extra Packages for Enterprise Linux
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=2255207 third party advisory issue tracking
https://github.com/tats/w3m/commit/edc602651c506aeeb60544b55534dd1722a340d3 patch
https://github.com/tats/w3m/issues/268 patch issue tracking exploit
https://github.com/tats/w3m/pull/273 patch issue tracking
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AULOBQJLXE2KCT5UVQMKGEFL4GFIAOED/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TODROGVCWZ435HQIZE6ARQC5LPQLIA5C/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MKFZQUK7FPWWJQYICDZZ4YWIPUPQ2D3R/

Frequently Asked Questions

What is the severity of CVE-2023-4255?
CVE-2023-4255 has been scored as a medium severity vulnerability.
How to fix CVE-2023-4255?
To fix CVE-2023-4255, 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-2023-4255 being actively exploited in the wild?
It is possible that CVE-2023-4255 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-4255?
CVE-2023-4255 affects n/a w3m, Fedora Fedora, Fedora Extra Packages for Enterprise Linux.
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