6.5

CVE-2020-21817: gnu libredwg NULL Pointer Dereference

CVSS: 6.5v3.1MediumModified
Published 17-05-2021Last modified 09-07-2026
Open JSON

Vulnerability summary

CVE-2020-21817 is a medium (CVSS 6.5) NULL Pointer Dereference vulnerability in gnu libredwg. EPSS estimates a 0.91% chance of exploitation in the next 30 days, higher than 59.3% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
36/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.91%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Timeline

  1. 17-05-2021
    PublishedVulnerability first disclosed.
  2. 09-07-2026
    Last modifiedVulnerability information updated.

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).

CVSS metrics

2 scores · 1 source · 2 versions

EPSS trend

Probability

0.91%

Chance of exploitation in the next 30 days

Percentile

59%

Versus all other CVEs

30-day change

0.00 pp

From 0.91% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.91%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Libredwg

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Gnu1 product

1 vendor · 1 product

References

1 links