CVE-2021-40647
CVE-2021-40647 is a medium-severity vulnerability in Man2html Project Man2html with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- EPSS exploit prediction: 0% (23rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Man2html Project Man2html
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is CVE-2021-40647?
- 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.
- How severe is CVE-2021-40647?
- CVE-2021-40647 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-40647 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-40647?
- CVE-2021-40647 affects Man2html Project Man2html. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-40647?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-40647 published?
- CVE-2021-40647 was published on 2022-09-09 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:man2html_project:man2html:1.6g:*:*:*:*:*:*:*
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- CVE-2021-40648 — Medium (CVSS 5.5): In man2html 1.6g, a filename can be created to overwrite the previous size parameter of the next chunk and the fd, bk,…
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