Rsync < 3.4.3 Out-of-Bounds Array Read via recv_files()
Rsync version 3.4.2 and prior contain a receiver-side out-of-bounds array read vulnerability in recv_files() in receiver.c that allows a malicious rsync server to crash the rsync client process. Attackers can exploit the vulnerability by setting CF_INC_RECURSE in compatibility flags and sending a specially crafted file list where the first sorted entry is not the leading dot directory, followed by a transfer record with ndx=0 and an iflag word without ITEM_TRANSFER, causing the receiver to read 8 bytes before the allocated pointer array and dereference an invalid pointer at an unmapped address, resulting in a deterministic SIGSEGV crash of the rsync client.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-43620
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 7 Nov 2026, 10:49 UTC · Revision 1
Source evidence
Rsync < 3.4.3 Out-of-Bounds Array Read via recv_files()
core-osv · Original sourcePublished 20 May 2026, 00:47 UTC
Rsync version 3.4.2 and prior contain a receiver-side out-of-bounds array read vulnerability in recv_files() in receiver.c that allows a malicious rsync server to crash the rsync client process. Attackers can exploit the vulnerability by setting CF_INC_RECURSE in compatibility flags and sending a specially crafted file list where the first sorted entry is not the leading dot directory, followed by a transfer record with ndx=0 and an iflag word without ITEM_TRANSFER, causing the receiver to read 8 bytes before the allocated pointer array and dereference an invalid pointer at an unmapped address, resulting in a deterministic SIGSEGV crash of the rsync client.
osv:CVE-2026-43620
Complete source record
{
"id": "30661c951daa2ed79a91970f28781c7ae48810518a5f2bbe7bdabc9907b78775",
"url": "https://osv.dev/vulnerability/CVE-2026-43620",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Rsync < 3.4.3 Out-of-Bounds Array Read via recv_files()",
"summary": "Rsync version 3.4.2 and prior contain a receiver-side out-of-bounds array read vulnerability in recv_files() in receiver.c that allows a malicious rsync server to crash the rsync client process. Attackers can exploit the vulnerability by setting CF_INC_RECURSE in compatibility flags and sending a specially crafted file list where the first sorted entry is not the leading dot directory, followed by a transfer record with ndx=0 and an iflag word without ITEM_TRANSFER, causing the receiver to read 8 bytes before the allocated pointer array and dereference an invalid pointer at an unmapped address, resulting in a deterministic SIGSEGV crash of the rsync client.",
"evidence": "osv:CVE-2026-43620",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-43620",
"aliases": [
"CVE-2026-43620",
"GHSA-28pw-r563-rxvm"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://git.samba.org/rsync.git/",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"last_affected": "de3cc03b03be153092f266aa1117b4706947ed07"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "3.4.2"
}
],
"source": "CPE_RANGE"
}
]
}
},
{
"repo": "https://github.com/rsyncproject/rsync",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "2c7777aaa62abeb1bca192da345e6e8c685e872a"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "3.4.2"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "2c7777aaa62abeb1bca192da345e6e8c685e872a"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v3.4.3"
}
]
}
}
],
"versions": [
"v3.2.7",
"v3.4.1",
"v3.4.2",
"v3.4.0",
"v3.3.0",
"v3.3.0pre1",
"v3.2.7pre1",
"v3.2.6",
"v3.2.5",
"v3.2.5pre2",
"v3.2.5pre1",
"v3.2.4",
"v3.2.4pre4",
"v3.2.4pre3",
"v3.2.4pre2",
"v3.2.4pre1",
"v3.2.3",
"v3.2.3pre1",
"v3.2.2",
"v3.2.2pre3",
"v3.2.2pre2",
"v3.2.2pre1",
"v3.2.1",
"v3.2.1pre1",
"v3.2.0",
"v3.2.0pre3",
"v3.2.0pre2",
"v3.2.0pre1",
"v3.1.3",
"v3.1.3pre1",
"v3.1.2",
"v3.1.2pre1",
"v3.1.1",
"v3.1.1pre2",
"v3.1.1pre1",
"v3.1.0",
"v3.1.0pre1",
"v3.0.3",
"v3.0.3pre3",
"v3.0.3pre2",
"v3.0.3pre1",
"v3.0.2",
"v3.0.1",
"v3.0.1pre3",
"v3.0.1pre2",
"v3.0.1pre1",
"v3.0.0",
"v3.0.0pre10",
"v3.0.0pre9",
"v3.0.0pre8",
"v3.0.0pre7",
"v3.0.0pre6",
"v3.0.0pre5",
"v3.0.0pre4",
"v3.0.0pre3",
"v3.0.0pre2",
"v3.0.0pre1",
"v2.6.9",
"v2.6.9pre3",
"v2.6.9pre2",
"v2.6.9pre1",
"v2.6.8",
"v2.6.8pre1",
"v2.6.7",
"v2.6.7pre3",
"v2.6.7pre2",
"v2.6.7pre1",
"v2.6.6pre1",
"v2.6.5",
"v2.6.5pre2",
"v2.6.5pre1",
"v2.6.4",
"v2.6.4pre4",
"v2.6.4pre3",
"v2.6.4pre2",
"v2.6.4pre1",
"v2.6.3",
"v2.6.3pre2",
"v2.6.3pre1",
"v2.6.2",
"v2.6.2pre1",
"v2.6.1",
"v2.6.1pre2",
"v2.6.1pre1",
"v2.6.0",
"v2.6.0pre2",
"v2.6.0pre1",
"v2.5.6",
"v2.5.5",
"v2.5.5.rc1",
"v2.5.4",
"v2.5.4pre1",
"v2.5.3",
"v2.5.3pre1",
"v2.5.2",
"v2.5.2pre3",
"v2.5.2pre2",
"v2.5.2pre1",
"v2.5.1",
"v2.5.1pre3",
"v2.5.1pre2",
"v2.5.1pre1",
"v2.5.0",
"v2.4.7pre4",
"v2.4.7pre2",
"mbp_bk_export0",
"v2.4.6",
"v2.4.5",
"v2.4.4",
"v2.4.3",
"v2.4.2",
"v2.4.1",
"v2.4.0",
"v2.3.2",
"v2.3.1",
"v2.3.0",
"v2.2.1",
"v2.2.0",
"v2.1.1",
"v2.1.0",
"v2.0.19",
"v2.0.18",
"v2.0.17",
"v2.0.16",
"v2.0.15",
"v2.0.14",
"v2.0.13",
"v2.0.12",
"v2.0.11",
"v2.0.10",
"v2.0.9",
"v2.0.8",
"v2.0.7",
"v2.0.6",
"v2.0.5",
"v2.0.4",
"v2.0.3",
"v2.0.2",
"v2.0.1",
"v2.0.0",
"v1.7.4",
"v1.7.3",
"v1.7.2",
"v1.7.1",
"v1.7.0",
"v1.6.9",
"v1.6.8",
"v1.6.7",
"v1.6.6",
"v1.6.5",
"v1.6.4"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-43620.json"
}
}
],
"modified": "2026-10-28T02:30:50.460453083Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43620.json",
"https://github.com/RsyncProject/rsync/releases/tag/v3.4.3",
"https://github.com/RsyncProject/rsync/security/advisories/GHSA-28pw-r563-rxvm",
"https://nvd.nist.gov/vuln/detail/CVE-2026-43620",
"https://www.vulncheck.com/advisories/rsync-out-of-bounds-array-read-via-recv-files",
"https://github.com/RsyncProject/rsync"
],
"provider_metadata": {
"cwe_ids": [
"CWE-125"
],
"cna_assigner": "VulnCheck",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43620.json"
}
},
"related_cves": [
{
"value": "CVE-2026-43620",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 519041,
"published_at": "2026-05-20T00:47:57.086+00:00"
}