Evidence used
- No CISA KEV confirmation is currently recorded.
- Exploitation requires an existing local or physical foothold with privileges.
- EPSS is 0.13% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-43619High confidence
Rsync < 3.4.3 Symlink Race Condition via Path-Based Syscalls
RsyncProject · rsync
Official source article: GitHub GHSA-4H9M-W5FF-J735 ↗. Check the applicable product and release in the original source.
7.2HighCVSS 4.0
Patch only the product branches with a verified fix
Fix availability varies by productHigh technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 17 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityHigh→Operational priority:Medium, lowered one band.downgradedsince 14 Jul 2026
Compensating controls
- Apply the linked authoritative mitigation while planning the permanent fix.
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs RsyncProject rsync and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Remediation availability differs by product scope
Verified remediation exists for at least one product or source, but 17 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
- Red Hat Product Security: 17 affected or under-investigation product states without a fixed product state in the same current advisory
Distribution package intelligence
8 package statesRelease-specific package status
Alpine, Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.
Repository candidate not checked
A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.
| Distribution release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Alpine v3.23v3.23 · main | rsync | Vendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected. | 3.4.3-r0 | Alpine Security Database ↗Source updated 3 Oct 2026 |
| Alpine v3.22v3.22 · main | rsync | Vendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected. | 3.4.3-r0 | Alpine Security Database ↗Source updated 3 Oct 2026 |
| Alpine v3.21v3.21 · main | rsync | Vendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected. | 3.4.3-r0 | Alpine Security Database ↗Source updated 3 Oct 2026 |
| Debian trixietrixie · source | rsync | Vendor fix publishedDebian records a fixed source-package version for this release. | 3.4.1+ds1-5+deb13u3 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian bookwormbookworm · source | rsync | Vendor fix publishedDebian records a fixed source-package version for this release. | 3.2.7-1+deb12u5 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian forkyforky · source | rsync | Vendor fix publishedDebian records a fixed source-package version for this release. | 3.4.3+ds1-1 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian sidsid · source | rsync | Vendor fix publishedDebian records a fixed source-package version for this release. | 3.4.3+ds1-1 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | rsync | Vendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree. | 3.2.7-1ubuntu1.4 | Canonical Ubuntu Security ↗Source updated 5 Oct 2026 |
Direct vendor intelligence
1 currentAuthoritative vendor CSAF and VEX advisories
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
CVE-2026-43619 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityrsync: rsync: Symlink race vulnerability allows unauthorized file operations
The vendor explicitly identifies these products as affected by this CVE.
- rsync as a component of Red Hat Enterprise Linux 10
- rsync-daemon as a component of Red Hat Enterprise Linux 10
- rsync-rrsync as a component of Red Hat Enterprise Linux 10
- rsync.src as a component of Red Hat Enterprise Linux 10
- rsync as a component of Red Hat Enterprise Linux 6
- rsync.src as a component of Red Hat Enterprise Linux 6
- rsync as a component of Red Hat Enterprise Linux 7
- rsync.src as a component of Red Hat Enterprise Linux 7
- rsync as a component of Red Hat Enterprise Linux 8
- rsync-daemon as a component of Red Hat Enterprise Linux 8
- rsync.src as a component of Red Hat Enterprise Linux 8
- rsync as a component of Red Hat Enterprise Linux 9
- Summary
- A flaw was found in rsync. A local attacker with filesystem access on the daemon host can exploit a symlink race vulnerability (CWE-367 Time-of-check to time-of-use) in rsync daemons configured with 'use chroot = no'. This allows the attacker to redirect path-based system calls, such as chmod, lchown, or unlink, outside the intended module. This could lead to unauthorized file operations or other security bypasses.
- Remediation
- To mitigate this issue, ensure that the `rsync` daemon is configured with `use chroot = yes`. This can be achieved by editing the `rsyncd.conf` file, typically located at `/etc/rsyncd.conf`, and setting `use chroot = yes` within the relevant module configuration. After modifying the configuration, the `rsync` service must be restarted for the changes to take effect. This may temporarily interrupt active `rsync` operations.
High technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 17 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Fix availability varies by product01
What, why and how
Rsync version 3.4.2 and prior contain symlink race condition vulnerabilities in path-based system calls including chmod, lchown, utimes, rename, unlink, mkdir, symlink, mknod, link, rmdir, and lstat that allow local attackers to redirect operations to files outside the exported rsync module. Attackers with local filesystem access can exploit the timing window between path resolution and syscall execution by swapping symlinks to apply sender-supplied permissions, ownership, timestamps, or filenames to arbitrary files outside the intended module boundary on rsync daemons configured with 'use chroot = no'.
What
Rsync version 3.4.2 and prior contain symlink race condition vulnerabilities in path-based system calls including chmod, lchown, utimes, rename, unlink, mkdir, symlink, mknod, link, rmdir, and lstat that allow local attackers to redirect operations to files outside the exported rsync module. Attackers with local filesystem access can exploit the timing window between path resolution and syscall execution by swapping symlinks to apply sender-supplied permissions, ownership, timestamps, or filenames to arbitrary files outside the intended module boundary on rsync daemons configured with 'use chroot = no'.
Why
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
How
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
Rsync version 3.4.2 and prior contain symlink race condition vulnerabilities in path-based system calls including chmod, lchown, utimes, rename, unlink, mkdir, symlink, mknod, link, rmdir, and lstat that allow local attackers to redirect operations to files outside the exported rsync module. Attackers with local filesystem access can exploit the timing window between path resolution and syscall execution by swapping symlinks to apply sender-supplied permissions, ownership, timestamps, or filenames to arbitrary files outside the intended module boundary on rsync daemons configured with 'use chroot = no'.
Why
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
How
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- local access → Time-of-check Time-of-use (TOCTOU) Race Condition → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Local
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- None
- Attack complexity
- High: exploitation depends on specific conditions
- Security boundary
- Not a CVSS 4.0 base metric
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-367 ↗
CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NCommon Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.
AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.ATPresentAttack requirements: A particular deployment or execution condition must be present.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VIHighVulnerable-system integrity: A successful attack can cause a major loss.VANoneVulnerable-system availability: No direct loss is represented by this metric.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: No direct loss is represented by this metric.- Post-exploitation / living off the land
- The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Fix availability varies by product
- Affected
- rsync as a component of Red Hat Enterprise Linux 10
- rsync-daemon as a component of Red Hat Enterprise Linux 10
- rsync-rrsync as a component of Red Hat Enterprise Linux 10
- rsync.src as a component of Red Hat Enterprise Linux 10
- rsync as a component of Red Hat Enterprise Linux 6
- rsync.src as a component of Red Hat Enterprise Linux 6
- rsync as a component of Red Hat Enterprise Linux 7
- rsync.src as a component of Red Hat Enterprise Linux 7
- rsync as a component of Red Hat Enterprise Linux 8
- rsync-daemon as a component of Red Hat Enterprise Linux 8
- rsync.src as a component of Red Hat Enterprise Linux 8
- rsync as a component of Red Hat Enterprise Linux 9
- rsync-daemon as a component of Red Hat Enterprise Linux 9
- rsync-rrsync as a component of Red Hat Enterprise Linux 9
- rsync.src as a component of Red Hat Enterprise Linux 9
- openshift/ose-rhel-coreos-8 as a component of Red Hat OpenShift Container Platform 4
- openshift/ose-rhel-coreos-9 as a component of Red Hat OpenShift Container Platform 4
- Action
- Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
- Workaround
- To mitigate this issue, ensure that the `rsync` daemon is configured with `use chroot = yes`. This can be achieved by editing the `rsyncd.conf` file, typically located at `/etc/rsyncd.conf`, and setting `use chroot = yes` within the relevant module configuration. After modifying the configuration, the `rsync` service must be restarted for the changes to take effect. This may temporarily interrupt active `rsync` operations.
04
Evidence and provenance
Published 20 May 2026 · Last source change 14 Jul 2026, 20:01 UTC · CWE-367 · Time-of-check Time-of-use (TOCTOU) Race Condition
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-31010
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- Affected versionsThe structured affected or fixed version information changed.Red Hat Product Security ↗
- Before
- rsync as a component of Red Hat Enterprise Linux 10; rsync-daemon as a component of Red Hat Enterprise Linux 10; rsync-rrsync as a component of Red Hat Enterprise Linux 10; rsync.src as a component of Red Hat Enterprise Linux 10; rsync as a component of Red Hat Enterprise Linux 6; rsync.src as a component of Red Hat Enterprise Linux 6; rsync as a component of Red Hat Enterprise Linux 7; rsync.src as a component of Red Hat Enterprise Linux 7; rsync as a component of Red Hat Enterprise Linux 8; rsync-daemon as a component of Red Hat Enterprise Linux 8; rsync.src as a component of Red Hat Enterprise Linux 8; rsync as a component of Red Hat Enterprise Linux 9; rsync-daemon as a component of Red Hat Enterprise Linux 9; rsync-rrsync as a component of Red Hat Enterprise Linux 9; rsync.src as a component of Red Hat Enterprise Linux 9; openshift/ose-rhel-coreos-9 as a component of Red Hat OpenShift Container Platform 4
- After
- rsync as a component of Red Hat Enterprise Linux 10; rsync-daemon as a component of Red Hat Enterprise Linux 10; rsync-rrsync as a component of Red Hat Enterprise Linux 10; rsync.src as a component of Red Hat Enterprise Linux 10; rsync as a component of Red Hat Enterprise Linux 6; rsync.src as a component of Red Hat Enterprise Linux 6; rsync as a component of Red Hat Enterprise Linux 7; rsync.src as a component of Red Hat Enterprise Linux 7; rsync as a component of Red Hat Enterprise Linux 8; rsync-daemon as a component of Red Hat Enterprise Linux 8; rsync.src as a component of Red Hat Enterprise Linux 8; rsync as a component of Red Hat Enterprise Linux 9; rsync-daemon as a component of Red Hat Enterprise Linux 9; rsync-rrsync as a component of Red Hat Enterprise Linux 9; rsync.src as a component of Red Hat Enterprise Linux 9; openshift/ose-rhel-coreos-8 as a component of Red Hat OpenShift Container Platform 4; openshift/ose-rhel-coreos-9 as a component of Red Hat OpenShift Container Platform 4
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.