llama.cpp — security advisory
llama.cpp builds b4882 through b9058 contain a heap buffer overflow vulnerability in the KV cache state restore path where the state_read_data() function computes write size without overflow checking, allowing attackers with write access to the slot_save_path directory to corrupt heap memory. Attackers can craft malicious state files where cell_count multiplication overflows or exceeds tensor buffer allocation to write attacker-controlled bytes past buffer boundaries, potentially resulting in heap metadata corruption, model weight corruption, or arbitrary code execution via function pointer overwrite.
- Products
- llama.cpp
- Affected versions
- 10438+dfsg-1, 10438+dfsg-1ubuntu1, 5882+dfsg-2, 8064+dfsg-1ubuntu1, 8681+dfsg-1, 9721+dfsg-1ubuntu1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-43629
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:44 UTC · Revision 1
Source evidence
llama.cpp builds b4882 through b9058 contain a heap buffer overflow vulnerability in the KV cache state restore path where the state_read_data() function computes write size without overflow checking, allowing attackers with write access to the slot_save_path directory to corrupt heap memory. Attackers can craft malicious state files where cell_count multiplication overflows or exceeds tensor buffer allocation to write attacker-controlled bytes past buffer boundaries, potentially resulting in heap metadata corruption, model weight corruption, or arbitrary code execution via function pointer overwrite.
osv:UBUNTU-CVE-2026-43629
llama.cpp
Fixed versions: Not specified
llama.cpp
Fixed versions: Not specified
Complete source record
{
"id": "fd9268689cbe9a231a4f014c4045d2397bcd8bcd6adf8e1ab99d697c833163ed",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-43629",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-43629",
"summary": "llama.cpp builds b4882 through b9058 contain a heap buffer overflow vulnerability in the KV cache state restore path where the state_read_data() function computes write size without overflow checking, allowing attackers with write access to the slot_save_path directory to corrupt heap memory. Attackers can craft malicious state files where cell_count multiplication overflows or exceeds tensor buffer allocation to write attacker-controlled bytes past buffer boundaries, potentially resulting in heap metadata corruption, model weight corruption, or arbitrary code execution via function pointer overwrite.",
"evidence": "osv:UBUNTU-CVE-2026-43629",
"products": [
{
"name": {
"value": "llama.cpp",
"evidence": "/affected/0/package/name"
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"prerequisites": [],
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"affected_versions": [
{
"value": "8681+dfsg-1",
"evidence": "/affected/0/versions"
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{
"value": "9721+dfsg-1ubuntu1",
"evidence": "/affected/0/versions"
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{
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{
"name": {
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"affected_versions": [
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"evidence": "/affected/1/versions"
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"severity": "critical",
"structured": {
"id": "UBUNTU-CVE-2026-43629",
"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
},
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
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"affected": [
{
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"type": "ECOSYSTEM",
"events": [
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"package": {
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"purl": "pkg:deb/ubuntu/llama.cpp?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
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"versions": [
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"9721+dfsg-1ubuntu1",
"10438+dfsg-1",
"10438+dfsg-1ubuntu1"
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"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43629.json"
},
"ecosystem_specific": {
"binaries": [
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{
"binary_name": "llama.cpp",
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{
"binary_name": "llama.cpp-services",
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{
"binary_name": "llama.cpp-tests",
"binary_version": "10438+dfsg-1ubuntu1"
},
{
"binary_name": "llama.cpp-tools",
"binary_version": "10438+dfsg-1ubuntu1"
},
{
"binary_name": "llama.cpp-tools-extra",
"binary_version": "10438+dfsg-1ubuntu1"
},
{
"binary_name": "python3-gguf",
"binary_version": "10438+dfsg-1ubuntu1"
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}
},
{
"ranges": [
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"type": "ECOSYSTEM",
"events": [
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],
"package": {
"name": "llama.cpp",
"purl": "pkg:deb/ubuntu/llama.cpp?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
"5882+dfsg-2",
"8064+dfsg-1ubuntu1",
"8681+dfsg-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43629.json"
},
"ecosystem_specific": {
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"binary_name": "libllama0",
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},
{
"binary_name": "llama.cpp",
"binary_version": "8681+dfsg-1"
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{
"binary_name": "llama.cpp-examples",
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{
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{
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{
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],
"modified": "2026-10-17T12:58:55.490020064Z",
"provider": "osv",
"upstream": [
"CVE-2026-43629"
],
"references": [
"https://ubuntu.com/security/CVE-2026-43629",
"https://www.cve.org/CVERecord?id=CVE-2026-43629",
"https://github.com/Vladimir-tokarev-cyera/llama-cpp-security-patches"
]
},
"related_cves": [
{
"value": "CVE-2026-43629",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/1/score"
},
"source_id": "core-osv",
"document_id": 359176,
"published_at": "2026-08-06T22:17:00+00:00"
}