Libsixel prior to v1.8.3 contains a stack buffer overflow in the function gif_process_raster at fromgif.c.
Conclusion & alert: CVE-2020-21050 is rated High Exploit Risk (67.1/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.94%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2025-11-21 | 1.27% | 0.94% | -0.33% |
| 2 | 2025-11-18 | 0.94% | 1.27% | +0.33% |
| 3 | 2025-09-21 | — | 0.94% | — |
Full EPSS history (13 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.5 | 3.1 | MEDIUM |
|
2.8 | 3.6 | [email protected] |
| 4.3 | 2.0 | MEDIUM |
|
8.6 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2020-21050 not yet assigned priority: Debian including 1 source packages (libsixel), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2020-21050 |
ubuntu
|
medium | CVE-2020-21050 medium priority: Ubuntu including 1 source packages (libsixel), 15 status rows across 15 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 10, needs-triage 3, DNE 1, released 1. | https://ubuntu.com/security/CVE-2020-21050 |
| URL | Tags |
|---|---|
| https://bitbucket.org/netbsd/pkgsrc/commits/a27113e21179cbfbfae0c35f6a9edd6aa498faae | Broken Link |
| https://cwe.mitre.org/data/definitions/121.html | Technical Description |
| https://github.com/saitoha/libsixel/blob/master/ChangeLog | Release Notes Third Party Advisory |
| https://github.com/saitoha/libsixel/commit/7808a06b88c11dbc502318cdd51fa374f8cd47ee | Patch Third Party Advisory |
| https://github.com/saitoha/libsixel/issues/75 | Exploit Issue Tracking Patch Third Party Advisory |
| https://github.com/saitoha/libsixel/releases/tag/v1.8.5 | Release Notes Third Party Advisory |