CVE-2023-4255
W3m: out-of-bounds write in function checktype() in etc.c (incomplete fix for cve-2022-38223)
- 5.5MediumCVSS base score
- 0.32%Exploitation in 30 daysEPSS · top 74% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By redhat
- 5 months later
· 5 months later
Published
- 14 months later
· 14 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.32% · top 74% of all CVEs (11 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
w3m
All versions: affected
All versions: affected
Fedora · Extra Packages for Enterprise Linux
All versions: affected
References
References7
- RHBZ#2255207 (opens in a new tab)issue-trackingx_refsource_REDHATx_transferred
- https://github.com/tats/w3m/commit/edc602651c506aeeb60544b55534dd1722a340d3 (opens in a new tab)x_transferred
- https://github.com/tats/w3m/issues/268 (opens in a new tab)x_transferred
- https://github.com/tats/w3m/pull/273 (opens in a new tab)x_transferred
- https://lists.fedoraproject.org/archives/list/[email protected]/message/AULOBQJLXE2KCT5UVQMKGEFL4GFIAOED/ (opens in a new tab)x_transferred
- https://lists.fedoraproject.org/archives/list/[email protected]/message/TODROGVCWZ435HQIZE6ARQC5LPQLIA5C/ (opens in a new tab)x_transferred
- https://lists.fedoraproject.org/archives/list/[email protected]/message/MKFZQUK7FPWWJQYICDZZ4YWIPUPQ2D3R/ (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-54126 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-4255)Record last updated .