How severe is CVE-2020-21817?

CVE-2020-21817 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-21817 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-21817?

CVE-2020-21817 affects Gnu Libredwg. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-21817?

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

When was CVE-2020-21817 published?

CVE-2020-21817 was published on 2021-05-17 and last updated on 2026-07-05.

CVE-2020-21817

CVE-2020-21817 is a medium-severity vulnerability in Gnu Libredwg with a CVSS 3.x base score of 6.5. 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-476.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Gnu Libredwg
Published: 2021-05-17
Last modified: 2026-07-05

Description

A null pointer dereference issue exists in GNU LibreDWG 0.10.2641 via htmlescape ../../programs/escape.c:29. which causes a denial of service (application crash).

Frequently asked questions

What is CVE-2020-21817?: A null pointer dereference issue exists in GNU LibreDWG 0.10.2641 via htmlescape ../../programs/escape.c:29. which causes a denial of service (application crash).
How severe is CVE-2020-21817?: CVE-2020-21817 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-21817 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-21817?: CVE-2020-21817 affects Gnu Libredwg. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-21817?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-21817 published?: CVE-2020-21817 was published on 2021-05-17 and last updated on 2026-07-05.

References

Affected products (1)

cpe:2.3:a:gnu:libredwg:0.10.2641:*:*:*:*:*:*:*

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CVE-2023-36274 — High (CVSS 8.8): LibreDWG v0.11 to v0.12.5 was discovered to contain a heap buffer overflow via the function bit_write_TF at bits.c.

All CVEs affecting Gnu Libredwg →

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