How severe is CVE-2020-21048?

CVE-2020-21048 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-2020-21048 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-21048?

CVE-2020-21048 affects Saitoha Libsixel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-21048?

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

When was CVE-2020-21048 published?

CVE-2020-21048 was published on 2021-09-14 and last updated on 2026-06-17.

CVE-2020-21048

CVE-2020-21048 is a medium-severity vulnerability in Saitoha Libsixel 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.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Saitoha Libsixel
Published: 2021-09-14
Last modified: 2026-06-17

Description

An issue in the dither.c component of libsixel prior to v1.8.4 allows attackers to cause a denial of service (DOS) via a crafted PNG file.

Frequently asked questions

What is CVE-2020-21048?: An issue in the dither.c component of libsixel prior to v1.8.4 allows attackers to cause a denial of service (DOS) via a crafted PNG file.
How severe is CVE-2020-21048?: CVE-2020-21048 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-2020-21048 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-21048?: CVE-2020-21048 affects Saitoha Libsixel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-21048?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-21048 published?: CVE-2020-21048 was published on 2021-09-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:saitoha:libsixel:*:*:*:*:*:*:*:*

More vulnerabilities in Saitoha Libsixel

CVE-2019-19638 — Critical (CVSS 9.8): An issue was discovered in libsixel 1.8.2. There is a heap-based buffer overflow in the function load_pnm at frompnm.c,…
CVE-2019-19637 — Critical (CVSS 9.8): An issue was discovered in libsixel 1.8.2. There is an integer overflow in the function sixel_decode_raw_impl at…
CVE-2019-19636 — Critical (CVSS 9.8): An issue was discovered in libsixel 1.8.2. There is an integer overflow in the function sixel_encode_body at tosixel.c.
CVE-2019-19635 — Critical (CVSS 9.8): An issue was discovered in libsixel 1.8.2. There is a heap-based buffer overflow in the function sixel_decode_raw_impl…
CVE-2022-27046 — High (CVSS 8.8): libsixel 1.8.6 suffers from a Heap Use After Free vulnerability in in libsixel/src/dither.c:388.
CVE-2022-27044 — High (CVSS 8.8): libsixel 1.8.6 is affected by Buffer Overflow in libsixel/src/quant.c:876.

All CVEs affecting Saitoha Libsixel →