HighFix available
giflib — security advisory
A memory leak (out-of-memory) in gif2rgb in util/gif2rgb.c in giflib 5.1.4 allows remote attackers trigger an out of memory exception or denial of service via a gif format file.
- Products
- giflib
- Affected versions
- 5.2.1-2.5, 5.2.1-2.5+deb12u1, 5.2.2-1, 6.1.3-1
- Fixed versions
- 5.2.2-1
- CVEs
- CVE-2021-40633
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:40 UTC · Revision 1
Source evidence
A memory leak (out-of-memory) in gif2rgb in util/gif2rgb.c in giflib 5.1.4 allows remote attackers trigger an out of memory exception or denial of service via a gif format file.
osv:DEBIAN-CVE-2021-40633
giflib
Fixed versions: Not specified
giflib
Fixed versions: 5.2.2-1
giflib
Fixed versions: 5.2.2-1
Complete source record
{
"id": "111a91147be55b6089955a8cdae385cc20293d5334854ead558e6c90d1203fe8",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-40633",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-40633",
"summary": "A memory leak (out-of-memory) in gif2rgb in util/gif2rgb.c in giflib 5.1.4 allows remote attackers trigger an out of memory exception or denial of service via a gif format file.",
"evidence": "osv:DEBIAN-CVE-2021-40633",
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"value": "5.2.1-2.5",
"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
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{
"value": "5.2.2-1",
"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
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{
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"severity": "high",
"structured": {
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"aliases": [
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"metrics": [
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"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"
}
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"affected": [
{
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{
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"package": {
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"ecosystem": "Debian:13"
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"package": {
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"database_specific": {
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],
"modified": "2026-10-23T18:03:33.070480501Z",
"provider": "osv",
"upstream": [
"CVE-2021-40633"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-40633"
]
},
"related_cves": [
{
"value": "CVE-2021-40633",
"evidence": "/upstream"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 421887,
"published_at": "2022-06-14T11:15:10.47+00:00"
}