Skip to content
Fencer Vulns
high 7.5

CVE-2026-70453 json

rsync < 3.5.0 Algorithmic Complexity DoS via hash_search()

published 2026-08-13 2 mo ago modified 2026-11-06 2 d ago also EUVD-2026-58051

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 48%
public exploits
0
none known

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.

Patch / fix

  • RsyncProject rsync 3.5.0
  • rsync Debian 12 3.5.0+ds1-0+deb12u1
  • rsync Debian 13 3.5.0+ds1-0+deb13u1
  • rsync Debian 14 3.5.0+ds1-1

debian advisories DEBIAN-CVE-2026-70453

  • rsync RHEL 8 3.1.3-28.el8_10
  • rsync-daemon RHEL 8 3.1.3-28.el8_10
  • rsync RHEL 10.2 3.5.0-3.el10_2
  • rsync-daemon RHEL 10.2 3.5.0-3.el10_2
  • rsync-rrsync RHEL 10.2 3.5.0-3.el10_2
  • rsync RHEL 9 3.2.7-1.el9_8
  • rsync-daemon RHEL 9 3.2.7-1.el9_8
  • rsync-rrsync RHEL 9 3.2.7-1.el9_8

red hat advisories RHSA-2026:74095RHSA-2026:67463RHSA-2026:67462

  • rsync SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 3.4.1-160000.6.1
  • rsync Linux Micro 6.0 3.2.7-8.1
  • rsync Linux Micro 6.1 3.3.0-slfo.1.1_7.1
  • rsync SLES for SAP 15 SP6, SLES 15 SP6-LTSS, SLE Module for Basesystem 15 SP7 3.2.7-150600.3.24.1
  • rsync SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +8 more 3.2.3-150400.3.34.1

suse advisories SUSE-SU-2026:23289-1SUSE-SU-2026:23323-1SUSE-SU-2026:23253-1SUSE-SU-2026:23254-1SUSE-SU-2026:3657-1SUSE-SU-2026:3634-1

  • rsync openSUSE Tumbleweed 3.5.1-1.1
  • rsync openSUSE Leap 16.0 3.4.1-160000.6.1

opensuse advisories openSUSE-SU-2026:11869-1openSUSE-SU-2026:21650-1

  • rsync AlmaLinux 8 3.1.3-28.el8_10
  • rsync-daemon AlmaLinux 8 3.1.3-28.el8_10
  • rsync AlmaLinux 9 3.2.7-1.el9_8
  • rsync-daemon AlmaLinux 9 3.2.7-1.el9_8
  • rsync-rrsync AlmaLinux 9 3.2.7-1.el9_8
  • rsync AlmaLinux 10 3.5.0-3.el10_2
  • rsync-daemon AlmaLinux 10 3.5.0-3.el10_2
  • rsync-rrsync AlmaLinux 10 3.5.0-3.el10_2

almalinux advisories ALSA-2026:74095ALSA-2026:67462ALSA-2026:67463

  • rsync Rocky Linux 8 3.1.3-28.el8_10
  • rsync Rocky Linux 9 3.2.7-1.el9_8
  • rsync Rocky Linux 10 3.5.0-3.el10_2

rocky linux advisories RLSA-2026:74095RLSA-2026:67462RLSA-2026:67463

  • rsync Alpine 3.24, Alpine 3.23, Alpine 3.22 +1 more 3.5.0-r0

alpine advisories ALPINE-CVE-2026-70453

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • rsync Azure Linux 3.0 3.5.0-1

azure linux advisories AZL-95855

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-70453 updated cvss 6.5

rsync: rsync: Denial of Service via Algorithmic Complexity

  • Red Hat Enterprise Linux 6 rsync Red Hat Enterprise Linux 7 rsync Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
    affected: workaround, no fix available
  • Red Hat Cost Management On-Premise 1 costmanagement/costmanagement-ui-rhel10 1791460851
    fixed: vendor fix RHSA-2026:79357
  • Red Hat Enterprise Linux AppStream (v. 9) rsync-daemon 3.2.7-1.el9_8, rsync-rrsync 3.2.7-1.el9_8
    fixed: vendor fix RHSA-2026:67462
  • Red Hat Enterprise Linux AppStream (v. 10) rsync-daemon 3.5.0-3.el10_2, rsync-rrsync 3.5.0-3.el10_2
    fixed: vendor fix RHSA-2026:67463
  • Red Hat Enterprise Linux BaseOS (v. 8) rsync 3.1.3-28.el8_10, rsync-daemon 3.1.3-28.el8_10
    fixed: vendor fix RHSA-2026:74095
  • Red Hat Enterprise Linux BaseOS (v. 9) rsync 3.2.7-1.el9_8
    fixed: vendor fix RHSA-2026:67462
  • Red Hat Enterprise Linux BaseOS (v. 10) rsync 3.5.0-3.el10_2
    fixed: vendor fix RHSA-2026:67463
  • Red Hat OpenShift Container Platform 4.22 rhcos 4.22.9.8.202609221802
    fixed: vendor fix RHSA-2026:71446

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
2 mo ago

Exploit prediction

0.59% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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

Affected products

  • RsyncProject rsync

Classification

Weakness
  • CWE-407 Inefficient Algorithmic Complexity

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.