Skip to main content

rsync EUVDEUVD-2026-58048

| CVE-2026-70456 HIGH
Out-of-bounds Write (CWE-787)
2026-08-13 VulnCheck
8.8
CVSS 4.0 · Vendor: VulnCheck
Share

Severity by source

Vendor (VulnCheck) PRIMARY
8.8 HIGH
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/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
vuln.today AI
8.2 HIGH

Network-reachable sender triggers heap corruption with no required privileges; availability impact is high (reliable crash), integrity low (bounded partial write), confidentiality not applicable.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
SUSE
8.2 HIGH
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Red Hat
8.2 HIGH
qualitative

Primary rating from Vendor (VulnCheck).

CVSS VectorVendor: VulnCheck

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
X

Lifecycle Timeline

3
Source Code Evidence Fetched
Aug 13, 2026 - 15:43 vuln.today
Analysis Generated
Aug 13, 2026 - 15:43 vuln.today
CVE Published
Aug 13, 2026 - 14:44 cve.org
HIGH 8.8

DescriptionCVE.org

rsync 3.0.1 before 3.5.0 contains an out-of-bounds write vulnerability in the read_args() function that allows a malicious sender to corrupt adjacent heap memory by sending a crafted argument list. When the argument count causes the argv allocation to be exactly full, the trailing NULL terminator is written one slot beyond the allocation boundary, corrupting adjacent heap memory.

AnalysisAI

Out-of-bounds heap write in rsync 3.0.1 through 3.4.x allows a malicious sender to corrupt adjacent heap memory by crafting an argument list that exactly fills the argv allocation in read_args(), causing the trailing NULL terminator to land one slot beyond the allocation boundary. Any rsync client performing a pull operation against an attacker-controlled or compromised server is exposed; heap corruption at this boundary can produce a crash (high availability impact) or potentially a write-what-where condition depending on heap layout. No public exploit code and no CISA KEV listing have been identified at time of analysis; rsync maintainers designated v3.5.0 a major security release, confirming patch availability.

Technical ContextAI

rsync is an open-source file synchronization utility that operates via a custom wire protocol, typically over TCP port 873 or tunneled through SSH. The vulnerability resides in the read_args() function, which processes the argument list transmitted by the sending side of an rsync session. When the sender delivers an argument count that causes the internal argv[] buffer allocation to be exactly full, an off-by-one condition arises: the NULL sentinel written to mark the end of the argument array is placed one element past the end of the heap-allocated buffer, overlapping the adjacent heap object. This is a textbook CWE-787 (Out-of-Bounds Write) rooted in an allocation size calculation that does not account for the mandatory terminating NULL. The affected CPE is cpe:2.3:a:rsyncproject:rsync:*:*:*:*:*:*:*:*, covering all versions from 3.0.1 up to but not including 3.5.0. The rsync trust model is central to risk: clients implicitly accept argument data from servers during the protocol handshake, giving a malicious server a direct path to trigger the flaw on any connecting client.

RemediationAI

Upgrade rsync to version 3.5.0 or later, available at https://github.com/RsyncProject/rsync/releases/tag/v3.5.0 and covered by security advisory GHSA-78jc-79jv-v6rw at https://github.com/RsyncProject/rsync/security/advisories/GHSA-78jc-79jv-v6rw. For systems where immediate upgrade is blocked - for example, due to distribution packaging lag - the most effective compensating control is to restrict rsync client operations to only explicitly trusted, authenticated servers: enforce SSH-tunneled rsync (rsync over SSH rather than the native rsync:// protocol) so that server identity is validated via SSH host key before any protocol data is exchanged; note that this does not eliminate the vulnerability if the SSH endpoint itself is later compromised, but it substantially raises the bar for exploitation. Blocking outbound TCP 873 at the perimeter prevents rsync:// connections but does not affect SSH-tunneled rsync. Automated cron-driven rsync pull jobs from third-party or public mirrors represent the highest-risk scenario and should be audited and temporarily suspended if a trusted upgrade path is unavailable.

More in Rsync

View all
CVE-2024-12085 HIGH POC
7.5 Jan 14

A flaw was found in rsync which could be triggered when rsync compares file checksums. Rated high severity (CVSS 7.5), t

CVE-2024-12084 CRITICAL POC
9.8 Jan 15

A heap-based buffer overflow flaw was found in the rsync daemon. Rated critical severity (CVSS 9.8), this vulnerability

CVE-2014-9512 MEDIUM POC
6.4 Feb 12

rsync 3.1.1 allows remote attackers to write to arbitrary files via a symlink attack on a file in the synchronization pa

CVE-2024-12087 HIGH POC
7.5 Jan 14

Server-to-client path traversal in rsync lets a malicious or compromised rsync server write files outside the client's i

CVE-2022-29154 HIGH POC
7.4 Aug 02

An issue was discovered in rsync before 3.2.5 that allows malicious remote servers to write arbitrary files inside the d

CVE-2014-2855 HIGH
7.8 Apr 23

The check_secret function in authenticate.c in rsync 3.1.0 and earlier allows remote attackers to cause a denial of serv

CVE-2024-12086 MEDIUM POC
6.8 Jan 14

A flaw was found in rsync. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authenticati

CVE-2017-16548 CRITICAL
9.8 Nov 06

The receive_xattr function in xattrs.c in rsync 3.1.2 and 3.1.3-development does not check for a trailing '\0' character

CVE-2017-17434 CRITICAL
9.8 Dec 06

The daemon in rsync 3.1.2, and 3.1.3-development before 2017-12-03, does not check for fnamecmp filenames in the daemon_

CVE-2017-15994 CRITICAL
9.8 Oct 29

rsync 3.1.3-development before 2017-10-24 mishandles archaic checksums, which makes it easier for remote attackers to by

CVE-2026-53790 CRITICAL
9.2 Aug 13

Arbitrary command execution in rsync before 3.5.0 arises from multiple unsanitized code paths - the RSYNC_CONNECT_PROG e

CVE-2026-70460 CRITICAL
9.2 Aug 13

Arbitrary file write in rsync 2.3.3 through 3.4.4 lets a malicious sender escape a daemon module's root by abusing symli

Vendor StatusVendor

SUSE

Severity: Important
Product Status
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS Affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS Affected
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS Affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS Affected
SUSE Linux Enterprise Micro 5.3 Affected

Share

EUVD-2026-58048 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy