Medium
Security advisory
In libsixel 1.8.6, sixel_encoder_output_without_macro (called from sixel_encoder_encode_frame in encoder.c) has a double free.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-46700
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:03 UTC · Revision 1
Source evidence
In libsixel 1.8.6, sixel_encoder_output_without_macro (called from sixel_encoder_encode_frame in encoder.c) has a double free.
osv:CVE-2021-46700
Complete source record
{
"id": "c616b3e8985335c157fbeb53a6693683d8cfb19649f54dd1af94eb5b2d3d01d4",
"url": "https://osv.dev/vulnerability/CVE-2021-46700",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-46700",
"summary": "In libsixel 1.8.6, sixel_encoder_output_without_macro (called from sixel_encoder_encode_frame in encoder.c) has a double free.",
"evidence": "osv:CVE-2021-46700",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2021-46700",
"aliases": [
"CVE-2021-46700"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/saitoha/libsixel",
"type": "GIT",
"events": [
{
"introduced": "6a5be8b72d84037b83a5ea838e17bcf372ab1d5f"
},
{
"last_affected": "6a5be8b72d84037b83a5ea838e17bcf372ab1d5f"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:saitoha:libsixel:1.8.6:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.8.6"
},
{
"last_affected": "1.8.6"
}
],
"source": "CPE_STRING"
}
]
}
}
],
"versions": [
"1.8.6",
"v1.8.6"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-46700.json"
}
}
],
"modified": "2026-10-20T10:55:10.895454422Z",
"provider": "osv",
"references": [
"https://github.com/saitoha/libsixel/issues/158"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-46700",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 387029,
"published_at": "2022-02-19T19:15:10.96+00:00"
}