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TI-2026-49226 Aliases CVE-2026-70453

rsync < 3.5.0 Algorithmic Complexity DoS via hash_search()

Priority MEDIUM 44CWE-407Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 7 fixed, 4 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-407.

Summary

rsync before 3.5.0 contains an algorithmic complexity vulnerability in the hash_search() function that allows a remote attacker to cause a denial of service by delivering a carefully constructed file list. A sender can exploit the quadratic-time worst-case behavior in hash lookups to exhaust receiver CPU resources with a modest number of crafted entries, causing a sustained denial of service.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00587 48th percentileScored 2026-11-07
Fix Partial rsync (RsyncProject): 3.5.0Red Hat: 5 advisoriesRed Hat: 7 fixed, 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Sambarsyncup to 3.4.43.5.0Patch availableCNA
  • rsync VendorSamba Affected up to 3.4.4 Fixed in 3.5.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*before 3.5.0VulnerableSamba
  • cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:* Versions before 3.5.0 Vulnerable ·Samba

Remediation

  • Fix · CNA rsync (RsyncProject) Fixed in 3.5.0

Red Hat 5 advisories

  • RHSA-2026:79357 Released 2026-10-08 · Red Hat rating Important
    Red Hat Cost Management On-Premise container image update
    • Red Hat Cost Management On-Premise 1 registry.redhat.io/costmanagement/costmanagement-ui-rhel10
  • RHSA-2026:74095 Released 2026-09-30 · Red Hat rating Important
    rsync security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS (v. 8) rsync-3.1.3-28.el8_10, rsync-daemon-3.1.3-28.el8_10
  • RHSA-2026:71446 Released 2026-09-29 · Red Hat rating Important
    OpenShift Container Platform 4.22.16 bug fix and security update
    • Red Hat OpenShift Container Platform 4.22 rhcos-aarch64-4.22.9.8.202609221802-0, rhcos-ppc64le-4.22.9.8.202609221802-0, rhcos-s390x-4.22.9.8.202609221802-0 +1
Show 2 more Red Hat advisories
  • RHSA-2026:67462 Released 2026-09-14 · Red Hat rating Important
    rsync security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) rsync-daemon-3.2.7-1.el9_8, rsync-rrsync-3.2.7-1.el9_8
    • Red Hat Enterprise Linux BaseOS (v. 9) rsync-3.2.7-1.el9_8
  • RHSA-2026:67463 Released 2026-09-14 · Red Hat rating Important
    rsync security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) rsync-daemon-3.5.0-3.el10_2, rsync-rrsync-3.5.0-3.el10_2
    • Red Hat Enterprise Linux BaseOS (v. 10) rsync-3.5.0-3.el10_2

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix yet
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Red Hat Cost Management On-Premise 1Fixed RHSA-2026:79357
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:67463
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:67462
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:67463
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:74095
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:67462
Red Hat OpenShift Container Platform 4.22Fixed RHSA-2026:71446

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-70453
  2. 2026-10-09 Fix available: RHSA-2026:79357 · Red Hat
  3. 2026-10-09 Fix available: Red Hat Cost Management On-Premise 1 · Red Hat
  4. 2026-11-06 Affected versions changed · Red Hat

References

Advisory 1

Other 1

  • TI-2024-11208 Rsync: heap buffer overflow in rsync due to improper checksum length handling CVSS 3.1CRITICAL 9.8
  • TI-2024-11209 Rsync: info leak via uninitialized stack contents CVSS 3.1HIGH 7.5
  • TI-2024-11212 Rsync: --safe-links option bypass leads to path traversal CVSS 3.1HIGH 7.5
  • TI-2024-11211 Rsync: path traversal vulnerability in rsync CVSS 3.1HIGH 7.5
  • TI-2024-11210 Rsync: rsync server leaks arbitrary client files CVSS 3.1MEDIUM 6.8
  • TI-2017-12160 The receive_xattr function in xattrs.c in rsync 3.1.2 and 3.1.3-development does not… CVSS 3.1CRITICAL 9.8
See all 56 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences