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Fencer Intel
high 7.5

CVE-2026-78002 json

Rsyslog: rsyslog: denial of service via heap buffer overflow in rainerscript replace() function

published 2mo ago modified 15h ago also EUVD-2026-67085 , GHSA-g72f-gc6v-f2w3

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository rsyslog/rsyslog. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.1%
EPSS 1.1% chance of exploitation in 30 days, percentile 65%
public exploits
0
none known

Summary

A flaw was found in rsyslog. An unauthenticated remote attacker can trigger a heap buffer overflow in the RainerScript `replace()` function by sending specially crafted syslog messages. This vulnerability arises from an incorrect buffer size calculation during string replacement, causing memory corruption. Successful exploitation can lead to a denial of service (DoS) for the affected system.

Patch / fix

  • Red Hat Red Hat Enterprise Linux 10 0:8.2510.0-5.el10_2.2, 0:8.2604.0-5.el10_3.1
  • Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support 0:8.2412.0-1.el10_0.2
  • Red Hat Red Hat Enterprise Linux 7 Extended Lifecycle Support 0:8.24.0-57.el7_9.4
  • Red Hat Red Hat Enterprise Linux 8 0:8.2102.0-15.el8_10.3
  • Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support 0:8.1911.0-7.el8_4.5
  • Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On 0:8.1911.0-7.el8_4.5
  • Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support 0:8.2102.0-7.el8_6.2
  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On 0:8.2102.0-7.el8_6.2
  • Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service 0:8.2102.0-13.el8_8.1
  • Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions 0:8.2102.0-13.el8_8.1
  • Red Hat Red Hat Enterprise Linux 9 0:8.2510.0-2.el9_8.2, 0:8.2604.0-4.el9_9.1
  • Red Hat Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions 0:8.2102.0-113.el9_2.3
  • Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions 0:8.2310.0-4.el9_4.2
  • Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support 0:8.2412.0-1.el9_6.2
  • Red Hat Red Hat Update Infrastructure 5 1790241900
  • rsyslog Debian 12 8.2302.0-1+deb12u2
  • rsyslog Debian 13 8.2504.0-1+deb13u2
  • rsyslog Debian 14 8.2608.0-4

debian advisories DEBIAN-CVE-2026-78002

  • rsyslog Ubuntu 22.04 LTS 8.2112.0-2ubuntu2.5
  • rsyslog Ubuntu 24.04 LTS 8.2312.0-3ubuntu9.4
  • rsyslog Ubuntu 26.04 LTS 8.2512.0-1ubuntu4.2
  • rsyslog Ubuntu Pro 16.04 LTS 8.16.0-1ubuntu3.1+esm3
  • rsyslog Ubuntu Pro 18.04 LTS 8.32.0-1ubuntu4.2+esm1
  • rsyslog Ubuntu Pro 20.04 LTS 8.2001.0-1ubuntu1.3+esm1

ubuntu advisories UBUNTU-CVE-2026-78002

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • rsyslog RHEL 8 8.2102.0-15.el8_10.3
  • rsyslog RHEL 10.2 8.2510.0-5.el10_2.2
  • rsyslog-relp RHEL 10.2 8.2510.0-5.el10_2.2
  • rsyslog-snmp RHEL 10.2 8.2510.0-5.el10_2.2
  • rsyslog-kafka RHEL 10.2 8.2510.0-5.el10_2.2
  • rsyslog-mysql RHEL 10.2 8.2510.0-5.el10_2.2
  • rsyslog-pgsql RHEL 10.2 8.2510.0-5.el10_2.2
  • rsyslog-crypto RHEL 10.2 8.2510.0-5.el10_2.2

red hat advisories RHSA-2026:84576RHSA-2026:81321RHSA-2026:80817RHSA-2026:69541RHSA-2026:69540

  • rsyslog SLES 16.0, SLES for SAP applications 16.0 8.2608.0-160000.1.1
  • rsyslog SLE Module for Server Applications 15 SP7, SLE Module for Package Hub 15 SP7, SLE Module for Basesystem 15 SP7 8.2608.0-150700.3.24.1

suse advisories SUSE-SU-2026:24598-1SUSE-SU-2026:4611-1

  • rsyslog openSUSE Leap 16.0 8.2608.0-160000.1.1

opensuse advisories openSUSE-SU-2026:22184-1

  • rsyslog AlmaLinux 8 8.2102.0-15.el8_10.3
  • rsyslog-relp AlmaLinux 8 8.2102.0-15.el8_10.3
  • rsyslog-snmp AlmaLinux 8 8.2102.0-15.el8_10.3
  • rsyslog-kafka AlmaLinux 8 8.2102.0-15.el8_10.3
  • rsyslog-mysql AlmaLinux 8 8.2102.0-15.el8_10.3
  • rsyslog-pgsql AlmaLinux 8 8.2102.0-15.el8_10.3
  • rsyslog-crypto AlmaLinux 8 8.2102.0-15.el8_10.3
  • rsyslog-gnutls AlmaLinux 8 8.2102.0-15.el8_10.3

almalinux advisories ALSA-2026:80817ALSA-2026:69540ALSA-2026:69541

  • rsyslog Rocky Linux 8 8.2102.0-15.el8_10.3
  • rsyslog Rocky Linux 9 8.2510.0-2.el9_8.2
  • rsyslog Rocky Linux 10 8.2510.0-5.el10_2.2

rocky linux advisories RLSA-2026:80817RLSA-2026:69540RLSA-2026:69541

  • rsyslog Alpine 3.24 8.2608.0-r0

alpine advisories ALPINE-CVE-2026-78002

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

  • rsyslog Azure Linux 3.0 8.2308.0-7

azure linux advisories AZL-98400

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

Is CVE-2026-78002 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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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-2026-78002 updated cvss 7.5

rsyslog: rsyslog: Denial of service via heap buffer overflow in RainerScript replace() function

  • Red Hat Enterprise Linux AppStream (v. 8) rsyslog 8.2102.0-15.el8_10.3
    fixed: vendor fix RHSA-2026:80817
  • Red Hat Enterprise Linux AppStream (v. 9) rsyslog 8.2510.0-2.el9_8.2, rsyslog 8.2604.0-4.el9_9.1, rsyslog-relp 8.2510.0-2.el9_8.2, rsyslog-relp 8.2604.0-4.el9_9.1, rsyslog-snmp 8.2510.0-2.el9_8.2, rsyslog-snmp 8.2604.0-4.el9_9.1, +33 more
    fixed: vendor fix RHSA-2026:69540
  • Red Hat Enterprise Linux AppStream (v. 10) rsyslog 8.2510.0-5.el10_2.2, rsyslog 8.2604.0-5.el10_3.1, rsyslog-relp 8.2510.0-5.el10_2.2, rsyslog-relp 8.2604.0-5.el10_3.1, rsyslog-snmp 8.2510.0-5.el10_2.2, rsyslog-snmp 8.2604.0-5.el10_3.1, +32 more
    fixed: vendor fix RHSA-2026:69541
  • Red Hat Enterprise Linux AppStream AUS (v.8.4) rsyslog 8.1911.0-7.el8_4.5, rsyslog-relp 8.1911.0-7.el8_4.5, rsyslog-snmp 8.1911.0-7.el8_4.5, rsyslog-kafka 8.1911.0-7.el8_4.5, rsyslog-mysql 8.1911.0-7.el8_4.5, rsyslog-pgsql 8.1911.0-7.el8_4.5, +11 more
    fixed: vendor fix RHSA-2026:95573
  • Red Hat Enterprise Linux AppStream AUS (v.8.6) rsyslog 8.2102.0-7.el8_6.2, rsyslog-relp 8.2102.0-7.el8_6.2, rsyslog-snmp 8.2102.0-7.el8_6.2, rsyslog-kafka 8.2102.0-7.el8_6.2, rsyslog-mysql 8.2102.0-7.el8_6.2, rsyslog-pgsql 8.2102.0-7.el8_6.2, +13 more
    fixed: vendor fix RHSA-2026:91582
  • Red Hat Enterprise Linux AppStream E4S (v.8.8) rsyslog 8.2102.0-13.el8_8.1, rsyslog-relp 8.2102.0-13.el8_8.1, rsyslog-snmp 8.2102.0-13.el8_8.1, rsyslog-kafka 8.2102.0-13.el8_8.1, rsyslog-mysql 8.2102.0-13.el8_8.1, rsyslog-pgsql 8.2102.0-13.el8_8.1, +13 more
    fixed: vendor fix RHSA-2026:87408
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) rsyslog 8.2102.0-113.el9_2.3, rsyslog-relp 8.2102.0-113.el9_2.3, rsyslog-snmp 8.2102.0-113.el9_2.3, rsyslog-kafka 8.2102.0-113.el9_2.3, rsyslog-mysql 8.2102.0-113.el9_2.3, rsyslog-pgsql 8.2102.0-113.el9_2.3, +14 more
    fixed: vendor fix RHSA-2026:86124
  • Red Hat Enterprise Linux AppStream E4S (v.9.4) rsyslog 8.2310.0-4.el9_4.2, rsyslog-relp 8.2310.0-4.el9_4.2, rsyslog-snmp 8.2310.0-4.el9_4.2, rsyslog-kafka 8.2310.0-4.el9_4.2, rsyslog-mysql 8.2310.0-4.el9_4.2, rsyslog-pgsql 8.2310.0-4.el9_4.2, +14 more
    fixed: vendor fix RHSA-2026:90349
show 8 more
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0) rsyslog 8.2412.0-1.el10_0.2, rsyslog-relp 8.2412.0-1.el10_0.2, rsyslog-snmp 8.2412.0-1.el10_0.2, rsyslog-kafka 8.2412.0-1.el10_0.2, rsyslog-mysql 8.2412.0-1.el10_0.2, rsyslog-pgsql 8.2412.0-1.el10_0.2, +13 more
    fixed: vendor fix RHSA-2026:81321
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) rsyslog 8.2412.0-1.el9_6.2, rsyslog-relp 8.2412.0-1.el9_6.2, rsyslog-snmp 8.2412.0-1.el9_6.2, rsyslog-kafka 8.2412.0-1.el9_6.2, rsyslog-mysql 8.2412.0-1.el9_6.2, rsyslog-pgsql 8.2412.0-1.el9_6.2, +14 more
    fixed: vendor fix RHSA-2026:84576
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) rsyslog 8.1911.0-7.el8_4.5, rsyslog-relp 8.1911.0-7.el8_4.5, rsyslog-snmp 8.1911.0-7.el8_4.5, rsyslog-kafka 8.1911.0-7.el8_4.5, rsyslog-mysql 8.1911.0-7.el8_4.5, rsyslog-pgsql 8.1911.0-7.el8_4.5, +11 more
    fixed: vendor fix RHSA-2026:95573
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) rsyslog 8.2102.0-7.el8_6.2, rsyslog-relp 8.2102.0-7.el8_6.2, rsyslog-snmp 8.2102.0-7.el8_6.2, rsyslog-kafka 8.2102.0-7.el8_6.2, rsyslog-mysql 8.2102.0-7.el8_6.2, rsyslog-pgsql 8.2102.0-7.el8_6.2, +13 more
    fixed: vendor fix RHSA-2026:91582
  • Red Hat Enterprise Linux AppStream TUS (v.8.8) rsyslog 8.2102.0-13.el8_8.1, rsyslog-relp 8.2102.0-13.el8_8.1, rsyslog-snmp 8.2102.0-13.el8_8.1, rsyslog-kafka 8.2102.0-13.el8_8.1, rsyslog-mysql 8.2102.0-13.el8_8.1, rsyslog-pgsql 8.2102.0-13.el8_8.1, +13 more
    fixed: vendor fix RHSA-2026:87408
  • Red Hat Enterprise Linux Server (v. 7 ELS) rsyslog 8.24.0-57.el7_9.4, rsyslog-relp 8.24.0-57.el7_9.4, rsyslog-kafka 8.24.0-57.el7_9.4, rsyslog-mysql 8.24.0-57.el7_9.4, rsyslog-pgsql 8.24.0-57.el7_9.4, rsyslog-gnutls 8.24.0-57.el7_9.4, +2 more Red Hat Enterprise Linux Server Optional (v. 7 ELS) rsyslog-snmp 8.24.0-57.el7_9.4, rsyslog-crypto 8.24.0-57.el7_9.4, rsyslog-libdbi 8.24.0-57.el7_9.4, rsyslog-mmaudit 8.24.0-57.el7_9.4, rsyslog-udpspoof 8.24.0-57.el7_9.4, rsyslog-mmjsonparse 8.24.0-57.el7_9.4, +4 more
    fixed: vendor fix RHSA-2026:96085
  • Red Hat Update Infrastructure 5 rhui5/haproxy-rhel9 1790241900
    fixed: vendor fix RHSA-2026:71603
  • Red Hat Enterprise Linux 6 rsyslog, rsyslog7, rsyslog-relp, rsyslog-snmp, rsyslog-mysql, rsyslog-pgsql, +9 more Red Hat Enterprise Linux AppStream (v. 8) rsyslog-relp 8.2102.0-15.el8_10.3, rsyslog-snmp 8.2102.0-15.el8_10.3, rsyslog-kafka 8.2102.0-15.el8_10.3, rsyslog-mysql 8.2102.0-15.el8_10.3, rsyslog-pgsql 8.2102.0-15.el8_10.3, rsyslog-crypto 8.2102.0-15.el8_10.3, +12 more Red Hat Enterprise Linux AppStream AUS (v.8.4) rsyslog-doc 8.1911.0-7.el8_4.5, rsyslog-udpspoof-debuginfo 8.1911.0-7.el8_4.5 Red Hat Enterprise Linux AppStream AUS (v.8.6) rsyslog-doc 8.2102.0-7.el8_6.2, rsyslog-udpspoof-debuginfo 8.2102.0-7.el8_6.2 Red Hat Enterprise Linux AppStream E4S (v.8.8) rsyslog-doc 8.2102.0-13.el8_8.1, rsyslog-kafka-debuginfo 8.2102.0-13.el8_8.1, rsyslog-gnutls-debuginfo 8.2102.0-13.el8_8.1, rsyslog-gssapi-debuginfo 8.2102.0-13.el8_8.1, rsyslog-mmaudit-debuginfo 8.2102.0-13.el8_8.1, rsyslog-mmfields-debuginfo 8.2102.0-13.el8_8.1, +1 more Red Hat Enterprise Linux AppStream E4S (v.9.2) rsyslog-doc 8.2102.0-113.el9_2.3, rsyslog-relp-debuginfo 8.2102.0-113.el9_2.3, rsyslog-snmp-debuginfo 8.2102.0-113.el9_2.3, rsyslog-kafka-debuginfo 8.2102.0-113.el9_2.3, rsyslog-mysql-debuginfo 8.2102.0-113.el9_2.3, rsyslog-pgsql-debuginfo 8.2102.0-113.el9_2.3, +12 more
    +8 more products
    Red Hat Enterprise Linux AppStream E4S (v.9.4) rsyslog-doc 8.2310.0-4.el9_4.2, rsyslog-relp-debuginfo 8.2310.0-4.el9_4.2, rsyslog-snmp-debuginfo 8.2310.0-4.el9_4.2, rsyslog-mysql-debuginfo 8.2310.0-4.el9_4.2, rsyslog-pgsql-debuginfo 8.2310.0-4.el9_4.2, rsyslog-mmaudit-debuginfo 8.2310.0-4.el9_4.2, +8 more Red Hat Enterprise Linux AppStream EUS (v. 10.0) rsyslog-debuginfo 8.2412.0-1.el10_0.2, rsyslog-relp-debuginfo 8.2412.0-1.el10_0.2, rsyslog-snmp-debuginfo 8.2412.0-1.el10_0.2, rsyslog-kafka-debuginfo 8.2412.0-1.el10_0.2, rsyslog-mysql-debuginfo 8.2412.0-1.el10_0.2, rsyslog-pgsql-debuginfo 8.2412.0-1.el10_0.2, +13 more Red Hat Enterprise Linux AppStream EUS (v.9.6) rsyslog-doc 8.2412.0-1.el9_6.2, rsyslog-relp-debuginfo 8.2412.0-1.el9_6.2, rsyslog-snmp-debuginfo 8.2412.0-1.el9_6.2, rsyslog-kafka-debuginfo 8.2412.0-1.el9_6.2, rsyslog-mysql-debuginfo 8.2412.0-1.el9_6.2, rsyslog-pgsql-debuginfo 8.2412.0-1.el9_6.2, +12 more Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) rsyslog-doc 8.1911.0-7.el8_4.5, rsyslog-udpspoof-debuginfo 8.1911.0-7.el8_4.5 Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) rsyslog-doc 8.2102.0-7.el8_6.2, rsyslog-udpspoof-debuginfo 8.2102.0-7.el8_6.2 Red Hat Enterprise Linux AppStream TUS (v.8.8) rsyslog-doc 8.2102.0-13.el8_8.1, rsyslog-kafka-debuginfo 8.2102.0-13.el8_8.1, rsyslog-gnutls-debuginfo 8.2102.0-13.el8_8.1, rsyslog-gssapi-debuginfo 8.2102.0-13.el8_8.1, rsyslog-mmaudit-debuginfo 8.2102.0-13.el8_8.1, rsyslog-mmfields-debuginfo 8.2102.0-13.el8_8.1, +1 more Red Hat Enterprise Linux Server Optional (v. 7 ELS) rsyslog-doc 8.24.0-57.el7_9.4 Red Hat Update Infrastructure 5 rhui5/cds-rhel9 1790241954, rhui5/rhua-rhel9 1790242004, rhui5/installer-rhel9 1790241922, rhui5/cds-kubernetes-rhel9 1790241897
    not affected: vulnerable code not present

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
2mo ago

Exploit prediction

1.06% chance of exploitation in the next 30 days, higher than 65% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support
  • Red Hat Red Hat Enterprise Linux 7 Extended Lifecycle Support
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  • Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On
  • Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On
  • Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service
  • Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions
  • Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions
  • Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support
  • Red Hat Red Hat Update Infrastructure 5
  • Red Hat Red Hat Enterprise Linux 6

Classification

Weakness
  • CWE-131 Incorrect Calculation of Buffer Size

References

Sources

Fencer Intel 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.

The maintainers of rsyslog/rsyslog published their own advisory on GitHub. Reviewed sources take precedence over it.