CVE-2026-45232
published 2026-05-20CVE-2026-45232: Rsync versions before 3.4.3 contain an off-by-one out-of-bounds stack write vulnerability in the establish_proxy_connection() function in socket.c that allows…
PriorityP419low3.7CVSS 3.1
AVNACHPRNUINSUCNINAL
EPSS
0.34%
25.9th percentile
Rsync versions before 3.4.3 contain an off-by-one out-of-bounds stack write vulnerability in the establish_proxy_connection() function in socket.c that allows network attackers to corrupt stack memory by sending a malformed HTTP proxy response. Attackers can exploit this by positioning themselves between the client and proxy or controlling the proxy server to send a response line of 1023 or more bytes without a newline terminator, causing a null byte to be written to an out-of-bounds stack address when the RSYNC_PROXY environment variable is set.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| rsyncproject | rsync | < 3.4.3 | 3.4.3 |
| samba | rsync | < 3.4.3 | 3.4.3 |
| samba | rsync | — | — |
| ubuntu | rsync | — | — |
CVSS provenance
nvdv3.13.7LOWCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
nvdv4.02.1LOWCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
vendor_ubuntu4.3MEDIUM
vendor_redhat2.1LOW
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Ubuntu
rsync regression
vendor_ubuntu·2026-06-16·CVSS 4.3
CVE-2025-10158 [MEDIUM] rsync regression
Title: rsync regression
Summary: USN-8349-1 introduced regressions in rsync.
USN-8349-1 fixed vulnerabilities in rsync. Unfortunately that update introduced multiple
regressions in rsync functionality. This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
Calum Hutton discovered that rsync contained a heap-based out-of-bounds
read when handling file transfers. A remote attacker with read access
to an rsync server could possibly use this issue to cause a denial of
service. (CVE-2025-10158)
Batuhan Sancak, Damien Neil, and Michael Stapelberg discovered that
rsync daemons configured without chroot protection were exposed to a
race condition on parent path components. A local attacker with write
access to a module could possibly use this issue to o
Ubuntu
rsync regression
vendor_ubuntu·2026-06-08·CVSS 4.3
CVE-2025-10158 [MEDIUM] rsync regression
Title: rsync regression
Summary: USN-8349-1 introduced regressions in rsync.
USN-8349-1 fixed vulnerabilities in rsync. The update introduced multiple
regressions in rsync functionality. This update fixes the problem.
Original advisory details:
Calum Hutton discovered that rsync contained a heap-based out-of-bounds
read when handling file transfers. A remote attacker with read access
to an rsync server could possibly use this issue to cause a denial of
service. (CVE-2025-10158)
Batuhan Sancak, Damien Neil, and Michael Stapelberg discovered that
rsync daemons configured without chroot protection were exposed to a
race condition on parent path components. A local attacker with write
access to a module could possibly use this issue to overwrite files,
obtain sensitive information, or esc
Ubuntu
rsync vulnerabilities
vendor_ubuntu·2026-06-01·CVSS 4.3
CVE-2026-43618 [MEDIUM] rsync vulnerabilities
Title: rsync vulnerabilities
Summary: Several security issues were fixed in rsync.
Calum Hutton discovered that rsync contained a heap-based out-of-bounds
read when handling file transfers. A remote attacker with read access
to an rsync server could possibly use this issue to cause a denial of
service. (CVE-2025-10158)
Batuhan Sancak, Damien Neil, and Michael Stapelberg discovered that
rsync daemons configured without chroot protection were exposed to a
race condition on parent path components. A local attacker with write
access to a module could possibly use this issue to overwrite files,
obtain sensitive information, or escalate privileges.
(CVE-2026-29518)
It was discovered that rsync did not properly validate a length value
while sorting extended attributes. An attacker could possi
Red Hat
rsync: Rsync: Denial of Service via malformed HTTP proxy response
vendor_redhat·2026-05-20·CVSS 2.1
CVE-2026-45232 [LOW] CWE-193 rsync: Rsync: Denial of Service via malformed HTTP proxy response
rsync: Rsync: Denial of Service via malformed HTTP proxy response
A flaw was found in rsync. A network attacker can exploit an off-by-one out-of-bounds stack write vulnerability in the `establish_proxy_connection()` function by sending a malformed HTTP proxy response. This occurs when the `RSYNC_PROXY` environment variable is set and the attacker sends a response line of 1023 or more bytes without a newline terminator. This can corrupt stack memory, potentially leading to a Denial of Service (DoS).
Mitigation: To mitigate this issue, ensure that the `RSYNC_PROXY` environment variable is not set. If rsync is configured to use an HTTP proxy via this variable, unsetting it will prevent exploitation. To unset the `RSYNC_PROXY` environment variable for the current session, use: `unset RSYNC_P
Ubuntu
rsync vulnerabilities
vendor_ubuntu·2026-05-20·CVSS 4.3
CVE-2026-43620 [MEDIUM] rsync vulnerabilities
Title: rsync vulnerabilities
Summary: Several security issues were fixed in rsync.
Calum Hutton discovered that rsync contained a heap-based out-of-bounds
read when handling file transfers. A remote attacker with read access
to an rsync server could possibly use this issue to cause a denial of
service. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS,
and Ubuntu 25.10. (CVE-2025-10158)
Batuhan Sancak, Damien Neil, and Michael Stapelberg discovered that
rsync daemons configured without chroot protection were exposed to a
race condition on parent path components. A local attacker with write
access to a module could possibly use this issue to overwrite files,
obtain sensitive information, or escalate privileges.
(CVE-2026-29518)
It was discovered that rsync did not properly val
VulDB
RsyncProject rsync up to 3.4.2 Environment Variable socket.c establish_proxy_connection RSYNC_PROXY off-by-one (GHSA-8f85-j2cv-59m8 / Nessus ID 315779)
vuldb·2026-06-02·CVSS 2.1
CVE-2026-45232 [LOW] RsyncProject rsync up to 3.4.2 Environment Variable socket.c establish_proxy_connection RSYNC_PROXY off-by-one (GHSA-8f85-j2cv-59m8 / Nessus ID 315779)
A vulnerability was found in RsyncProject rsync up to 3.4.2 and classified as problematic. Affected by this issue is the function establish_proxy_connection of the file socket.c of the component Environment Variable Handler. Executing a manipulation of the argument RSYNC_PROXY can lead to off-by-one.
This vulnerability is handled as CVE-2026-45232. The attack can be executed remotely. There is not any exploit available.
It is suggested to upgrade the affected component.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-45232 rsync-bpc: Rsync: Denial of Service via malformed HTTP proxy response [fedora-all]
bugzilla·2026-05-21·CVSS 2.1
CVE-2026-45232 [LOW] CVE-2026-45232 rsync-bpc: Rsync: Denial of Service via malformed HTTP proxy response [fedora-all]
CVE-2026-45232 rsync-bpc: Rsync: Denial of Service via malformed HTTP proxy response [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Bugzilla
CVE-2026-45232 rsync: Rsync: Denial of Service via malformed HTTP proxy response [fedora-all]
bugzilla·2026-05-21·CVSS 2.1
CVE-2026-45232 [LOW] CVE-2026-45232 rsync: Rsync: Denial of Service via malformed HTTP proxy response [fedora-all]
CVE-2026-45232 rsync: Rsync: Denial of Service via malformed HTTP proxy response [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Bugzilla
CVE-2026-45232 rsync-bpc: Rsync: Denial of Service via malformed HTTP proxy response [epel-all]
bugzilla·2026-05-21·CVSS 2.1
CVE-2026-45232 [LOW] CVE-2026-45232 rsync-bpc: Rsync: Denial of Service via malformed HTTP proxy response [epel-all]
CVE-2026-45232 rsync-bpc: Rsync: Denial of Service via malformed HTTP proxy response [epel-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Bugzilla
CVE-2026-45232 rsync: Rsync: Denial of Service via malformed HTTP proxy response
bugzilla·2026-05-20·CVSS 2.1
CVE-2026-45232 [LOW] CVE-2026-45232 rsync: Rsync: Denial of Service via malformed HTTP proxy response
CVE-2026-45232 rsync: Rsync: Denial of Service via malformed HTTP proxy response
Rsync versions before 3.4.3 contain an off-by-one out-of-bounds stack write vulnerability in the establish_proxy_connection() function in socket.c that allows network attackers to corrupt stack memory by sending a malformed HTTP proxy response. Attackers can exploit this by positioning themselves between the client and proxy or controlling the proxy server to send a response line of 1023 or more bytes without a newline terminator, causing a null byte to be written to an out-of-bounds stack address when the RSYNC_PROXY environment variable is set.
2026-05-20
Published