How severe is CVE-2021-40648?

CVE-2021-40648 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-2021-40648 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-2021-40648?

CVE-2021-40648 affects Man2html Project Man2html. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-40648?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-40648 published?

CVE-2021-40648 was published on 2022-09-09 and last updated on 2026-06-17.

CVE-2021-40648

CVE-2021-40648 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-20.

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-20
Affected product: Man2html Project Man2html
Published: 2022-09-09
Last modified: 2026-06-17

Description

In man2html 1.6g, a filename can be created to overwrite the previous size parameter of the next chunk and the fd, bk, fd_nextsize, bk_nextsize of the current chunk. The next chunk is then freed later on, causing a freeing of an arbitrary amount of memory.

Frequently asked questions

What is CVE-2021-40648?: In man2html 1.6g, a filename can be created to overwrite the previous size parameter of the next chunk and the fd, bk, fd_nextsize, bk_nextsize of the current chunk. The next chunk is then freed later on, causing a freeing of an arbitrary amount of memory.
How severe is CVE-2021-40648?: CVE-2021-40648 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-2021-40648 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-2021-40648?: CVE-2021-40648 affects Man2html Project Man2html. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-40648?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-40648 published?: CVE-2021-40648 was published on 2022-09-09 and last updated on 2026-06-17.

References

https://gist.github.com/untaman/cb58123fe89fc65e3984165db5d40933

Affected products (1)

cpe:2.3:a:man2html_project:man2html:1.6g:*:*:*:*:*:*:*

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