CVE-2020-21677
CVE-2020-21677 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. The underlying weakness is classified as CWE-787.
Key facts
- Severity: Medium (CVSS 3.x base score 6.5)
- CVSS v2: 4.3
- EPSS exploit prediction: 1% (55th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Saitoha Libsixel
- Published:
- Last modified:
Description
A heap-based buffer overflow in the sixel_encoder_output_without_macro function in encoder.c of Libsixel 1.8.4 allows attackers to cause a denial of service (DOS) via converting a crafted PNG file into Sixel format.
Frequently asked questions
- What is CVE-2020-21677?
- A heap-based buffer overflow in the sixel_encoder_output_without_macro function in encoder.c of Libsixel 1.8.4 allows attackers to cause a denial of service (DOS) via converting a crafted PNG file into Sixel format.
- How severe is CVE-2020-21677?
- CVE-2020-21677 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-2020-21677 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-21677?
- CVE-2020-21677 affects Saitoha Libsixel. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-21677?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2020-21677 published?
- CVE-2020-21677 was published on 2021-08-10 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:saitoha:libsixel:1.8.4:*:*:*:*:*:*:*
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 →
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