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Fencer Vulns
high 7.3

CVE-2026-5435 json

Potential buffer overflow in ns_sprintrrf TSIG handling path

published 2026-04-28 6 mo ago modified 2026-10-15 25 d ago also EUVD-2026-26036

cvss
7.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 14%
public exploits
0
none known

Summary

The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records.

Patch / fix

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP V3.1.6
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP V3.1.6
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP V3.1.6
  • glibc Debian 14 2.43-3

debian advisories DEBIAN-CVE-2026-5435

  • glibc Ubuntu 22.04 LTS 2.35-0ubuntu3.14
  • glibc Ubuntu 24.04 LTS 2.39-0ubuntu8.8
  • glibc Ubuntu 26.04 LTS 2.43-2ubuntu2.3

ubuntu advisories UBUNTU-CVE-2026-5435

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

  • glibc RHEL 9 2.34-274.el9_8
  • nscd RHEL 9 2.34-274.el9_8
  • libnsl RHEL 9 2.34-274.el9_8
  • nss_db RHEL 9 2.34-274.el9_8
  • nss_hesiod RHEL 9 2.34-274.el9_8
  • glibc-utils RHEL 9 2.34-274.el9_8
  • glibc-common RHEL 9 2.34-274.el9_8
  • glibc-benchtests RHEL 9 2.34-274.el9_8

red hat advisories RHSA-2026:42952RHSA-2026:42733RHSA-2026:42694RHSA-2026:12740

  • glibc SLES for SAP 15 SP6, SLES 15 SP6-LTSS, SLE Module for Development Tools 15 SP7 +1 more 2.38-150600.14.52.1
  • glibc SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +8 more 2.31-150300.104.1
  • glibc Linux Micro 6.0 2.38-14.1
  • glibc Linux Micro Extras 6.2 2.40-160000.6.1
  • glibc Linux Micro 6.1 2.38-slfo.1.1_9.1
  • glibc SLES LTSS Extended Security 12 SP5 2.22-114.49.1

suse advisories SUSE-SU-2026:3030-1SUSE-SU-2026:3029-1SUSE-SU-2026:2987-1SUSE-SU-2026:22523-1SUSE-SU-2026:22538-1SUSE-SU-2026:22453-1

  • glibc openSUSE Leap 16.0 2.40-160000.6.1
  • glibc-cross-s390x-src openSUSE Leap 16.0 2.40-160000.6.1
  • glibc-cross-aarch64-src openSUSE Leap 16.0 2.40-160000.6.1
  • glibc-cross-ppc64le-src openSUSE Leap 16.0 2.40-160000.6.1
  • glibc-cross-riscv64-src openSUSE Leap 16.0 2.40-160000.6.1
  • glibc openSUSE Tumbleweed 2.43-4.1

opensuse advisories openSUSE-SU-2026:21228-1openSUSE-SU-2026:11140-1

  • glibc AlmaLinux 10 2.39-128.el10_2.alma.1
  • libnsl AlmaLinux 10 2.39-128.el10_2.alma.1
  • nss_db AlmaLinux 10 2.39-128.el10_2.alma.1
  • nss_hesiod AlmaLinux 10 2.39-128.el10_2.alma.1
  • glibc-utils AlmaLinux 10 2.39-128.el10_2.alma.1
  • glibc-common AlmaLinux 10 2.39-128.el10_2.alma.1
  • glibc-benchtests AlmaLinux 10 2.39-128.el10_2.alma.1
  • glibc-gconv-extra AlmaLinux 10 2.39-128.el10_2.alma.1

almalinux advisories ALSA-2026:42694ALSA-2026:42733ALSA-2026:42952

  • glibc Rocky Linux 9 2.34-274.el9_8
  • glibc Rocky Linux 10 2.39-128.el10_2
  • glibc Rocky Linux 8 2.28-251.el8_10.40

rocky linux advisories RLSA-2026:42952RLSA-2026:42694RLSA-2026:42733

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-2026-5435 updated cvss 5.9

glibc: glibc: Out-of-bounds write via TSIG record processing

  • Red Hat Enterprise Linux 6 nscd, glibc, glibc-utils, compat-glibc, glibc-common Red Hat Enterprise Linux 7 nscd, glibc, glibc-utils, compat-glibc, glibc-common Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9
    affected: no fix available “Fix deferred”
  • Red Hat Cert Manager support for Red Hat OpenShift release 1.17 cert-manager/cert-manager-operator-rhel9 1791788287, cert-manager/jetstack-cert-manager-rhel9 1791371069, cert-manager/cert-manager-istio-csr-rhel9 1791378395, cert-manager/cert-manager-operator-bundle 1791970484, cert-manager/jetstack-cert-manager-acmesolver-rhel9 1791371080
    fixed: vendor fix RHSA-2026:82336
  • Red Hat Cert Manager support for Red Hat OpenShift release 1.18 cert-manager/cert-manager-operator-rhel9 1789029076, cert-manager/jetstack-cert-manager-rhel9 1791459711, cert-manager/cert-manager-istio-csr-rhel9 1791459759, cert-manager/cert-manager-operator-bundle 1791966259, cert-manager/jetstack-cert-manager-acmesolver-rhel9 1791459707
    fixed: vendor fix RHSA-2026:82354
  • Red Hat Cert Manager support for Red Hat OpenShift release 1.20 cert-manager/cert-manager-operator-rhel9 1790272426, cert-manager/cert-manager-operator-rhel9 1790589855, cert-manager/jetstack-cert-manager-rhel9 1790223279, cert-manager/jetstack-cert-manager-rhel9 1790589912, cert-manager/cert-manager-istio-csr-rhel9 1790223719, cert-manager/cert-manager-istio-csr-rhel9 1790589914, +2 more
    fixed: vendor fix RHSA-2026:72475
  • Red Hat Cost Management 4 costmanagement/costmanagement-metrics-rhel9-operator 1790844333
    fixed: vendor fix RHSA-2026:81201
  • Red Hat Discovery 2 discovery/discovery-ui-rhel9 1784821750, discovery/discovery-server-rhel9 1784821670
    fixed: vendor fix RHSA-2026:46836
  • Red Hat Enterprise Linux AppStream (v. 8) glibc-utils 2.28-251.el8_10.40, compat-libpthread-nonshared 2.28-251.el8_10.40
    fixed: vendor fix RHSA-2026:42733
  • Red Hat Enterprise Linux AppStream (v. 9) glibc-utils 2.34-274.el9_8, glibc-locale-source 2.34-274.el9_8
    fixed: vendor fix RHSA-2026:42952
show 12 more
  • Red Hat Enterprise Linux AppStream (v. 10) glibc-utils 2.39-128.el10_2, glibc-locale-source 2.39-128.el10_2
    fixed: vendor fix RHSA-2026:42694
  • Red Hat Enterprise Linux BaseOS (v. 8) nscd 2.28-251.el8_10.40, glibc 2.28-251.el8_10.40, libnsl 2.28-251.el8_10.40, nss_db 2.28-251.el8_10.40, glibc-common 2.28-251.el8_10.40, glibc-gconv-extra 2.28-251.el8_10.40, +3 more
    fixed: vendor fix RHSA-2026:42733
  • Red Hat Enterprise Linux BaseOS (v. 9) nscd 2.34-274.el9_8, glibc 2.34-274.el9_8, libnsl 2.34-274.el9_8, glibc-common 2.34-274.el9_8, glibc-gconv-extra 2.34-274.el9_8, glibc-all-langpacks 2.34-274.el9_8, +1 more
    fixed: vendor fix RHSA-2026:42952
  • Red Hat Enterprise Linux BaseOS (v. 10) glibc 2.39-128.el10_2, libnsl 2.39-128.el10_2, glibc-common 2.39-128.el10_2, glibc-gconv-extra 2.39-128.el10_2, glibc-all-langpacks 2.39-128.el10_2, glibc-minimal-langpack 2.39-128.el10_2
    fixed: vendor fix RHSA-2026:42694
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) nss_db 2.34-274.el9_8, nss_hesiod 2.34-274.el9_8, glibc-benchtests 2.34-274.el9_8
    fixed: vendor fix RHSA-2026:42952
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) nss_db 2.39-128.el10_2, nss_hesiod 2.39-128.el10_2, glibc-benchtests 2.39-128.el10_2
    fixed: vendor fix RHSA-2026:42694
  • Red Hat Enterprise Linux CRB (v. 8) nss_hesiod 2.28-251.el8_10.40, glibc-benchtests 2.28-251.el8_10.40
    fixed: vendor fix RHSA-2026:42733
  • Red Hat Hardened Images glibc 2.42-12.hum1, glibc32 2.42-12.hum1, glibc-utils 2.42-12.hum1, glibc-common 2.42-12.hum1, glibc-benchtests 2.42-12.hum1, glibc-gconv-extra 2.42-12.hum1, +5 more
    fixed: vendor fix RHSA-2026:12740
  • Red Hat Insights proxy 1.5 insights-proxy/insights-proxy-container-rhel9 1786433656
    fixed: vendor fix RHSA-2026:53371
  • Red Hat OpenShift distributed tracing 3.10.1 rhosdt/tempo-rhel9 1784775768, rhosdt/tempo-query-rhel9 1784775793, rhosdt/tempo-gateway-rhel9 1784775770, rhosdt/tempo-rhel9-operator 1784775782, rhosdt/tempo-operator-bundle 1784777166, rhosdt/tempo-gateway-opa-rhel9 1784775772, +3 more
    fixed: vendor fix RHSA-2026:50205
  • Red Hat Update Infrastructure 5 rhui5/cds-rhel9 1784794778, rhui5/rhua-rhel9 1784795076, rhui5/haproxy-rhel9 1784795112, rhui5/rhua-tp-rhel9 1787241260, rhui5/installer-rhel9 1784794289, rhui5/installer-tp-rhel9 1787135742, +2 more
    fixed: vendor fix RHSA-2026:44481
  • Red Hat Cert Manager support for Red Hat OpenShift release 1.20 cert-manager/jetstack-cert-manager-acmesolver-rhel9 1790223630 Red Hat Cost Management 4 costmanagement/costmanagement-metrics-operator-bundle 1790851152 Red Hat Hardened Images libnsl 2.42-12.hum1, nss_db 2.42-12.hum1, nss_hesiod 2.42-12.hum1, compat-libpthread-nonshared 2.42-12.hum1 Red Hat OpenShift AI (RHOAI) rhoai/odh-llama-stack-k8s-operator-rhel9 Red Hat OpenShift distributed tracing 3.10.1 rhosdt/opentelemetry-operator-bundle 1785744179, rhosdt/opentelemetry-target-allocator-rhel9 1785704551 Red Hat Update Infrastructure 5 rhui5/cds-tp-rhel9 1787241206
    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
6 mo ago

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CNA 3.1 7.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Affected products

  • The GNU C Library glibc
  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

Classification

Weakness

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.