glibc — security advisory
An off-by-one heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a message bigger than INT_MAX bytes, leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.
- Products
- glibc
- Affected versions
- 2.36-9, 2.36-9+deb12u1, 2.36-9+deb12u2, 2.36-9+deb12u3
- Fixed versions
- 2.36-9+deb12u4, 2.37-15
- CVEs
- CVE-2023-6779
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 15:53 UTC · Revision 1
Source evidence
An off-by-one heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a message bigger than INT_MAX bytes, leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.
osv:DEBIAN-CVE-2023-6779
glibc
Fixed versions: 2.36-9+deb12u4
glibc
Fixed versions: 2.37-15
glibc
Fixed versions: 2.37-15
Complete source record
{
"id": "b9607774ec6587dbbb9aa98c3bd9e93d18321c1e14a1edc47e79cb567ef3cf50",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2023-6779",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2023-6779",
"summary": "An off-by-one heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a message bigger than INT_MAX bytes, leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.",
"evidence": "osv:DEBIAN-CVE-2023-6779",
"products": [
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"value": "glibc",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
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"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
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"evidence": "/affected/0/versions"
},
{
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"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
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{
"name": {
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"evidence": "/affected/1/package/name"
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{
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],
"severity": "high",
"structured": {
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"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
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"events": [
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"package": {
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"ecosystem": "Debian:12"
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"versions": [
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"2.36-9+deb12u1",
"2.36-9+deb12u2",
"2.36-9+deb12u3"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-6779.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
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"package": {
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"purl": "pkg:deb/debian/glibc?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-6779.json"
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"ecosystem_specific": {
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{
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"package": {
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"purl": "pkg:deb/debian/glibc?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-6779.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T18:02:22.015077336Z",
"provider": "osv",
"upstream": [
"CVE-2023-6779"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2023-6779"
]
},
"related_cves": [
{
"value": "CVE-2023-6779",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 455979,
"published_at": "2024-01-31T14:15:48.7+00:00"
}