In man2html 1.6g, a specific string being read in from a file will overwrite the size…
Priority LOW 25CWE-787Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.
Summary
In man2html 1.6g, a specific string being read in from a file will overwrite the size parameter in the top chunk of the heap. This at least causes the program to segmentation abort if the heap size parameter isn't aligned correctly. In version before GLIBC version 2.29 and aligned correctly, it allows arbitrary write anywhere in the programs memory.
Why it matters now
EPSS 0.00337 27th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:man2html_project:man2html:1.6g:*:*:*:*:*:*:* | 1.6g | Vulnerable | Man2html Project |
- cpe:2.3:a:man2html_project:man2html:1.6g:*:*:*:*:*:*:* Versions 1.6g Vulnerable ·Man2html Project
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2021-40647
- 2026-10-03 Alias added: GHSA-p3mv-74p6-4mgc
References
More Man2html Project Man2html vulnerabilities
- TI-2021-17627 In man2html 1.6g, a filename can be created to overwrite the previous size parameter of… CVSS 3.1MEDIUM 5.5
Sources
- CVE-2021-40647 · CVE Program
- CVE-2021-40647 · NVD
- FIRST EPSS
- GHSA-p3mv-74p6-4mgc · GitHub Advisory Database · CC BY 4.0
- CVE-2021-40647 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences