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TI-2026-15397 Aliases CVE-2026-18798GHSA-3j55-qf57-hqc2

QUIC Server May Trigger Double Free When Processing INITIAL Packet

Priority MEDIUM 42CWE-415Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 11 fixed, 4 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-415 and the CVSS impact.

Summary

Issue summary: QUIC server may double free QRX (QUIC record layer RX) object when channel creation fails for initial packet. Impact summary: Double free leads to heap corruption, which typically results in termination of QUIC server process, leading to Denial of Service. There is so far no evidence that this double free is exploitable for remote code execution, thus it is considered highly improbable. CWE: CWE-415: Double Free Description: In order to validate initial packet, OpenSSL QUIC stack default packet handler (port_default_packet_handler()) creates a so-called QRX object. If the initial packet validates successfully with QRX object, the default packet handler proceeds to channel (connection object) creation. The QRX object used for packet validation is passed to port_bind_channel(), so it becomes part of the newly created connection. If port_bind_channel() fails, then it also frees the QRX object. Once port_bind_channel() returns, the port_default_packet_handler() detects the failure and proceeds to the error branch, where the same QRX object is freed for the second time. The failure in port_bind_channel() function can be induced with a relatively low effort by a malformed (non RFC 9000 compliant) INITIAL packet. If the packet carries DCID (destination connection ID) which is shorter than 8 bytes, then port_bind_channel() jumps to the error path after ossl_quic_lcidm_enrol_odcid() detects that the DCID has invalid length. FIPS impact: no The FIPS module is not affected, as the QUIC implementation is outside of the OpenSSL FIPS module boundary.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01697 77th percentileScored 2026-11-07
Fix Partial OpenSSL (OpenSSL): 4.0.2, 3.6.4, 3.5.8Red Hat: 16 advisoriesRed Hat: 11 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
OpenSSLOpenSSL4.0.0 to before 4.0.2; 3.6.0 to before 3.6.4; 3.5.0 to before 3.5.84.0.2, 3.6.4, 3.5.8Patch availableCNA
  • OpenSSL VendorOpenSSL Affected 4.0.0 to before 4.0.2; 3.6.0 to before 3.6.4; 3.5.0 to before 3.5.8 Fixed in 4.0.2, 3.6.4, 3.5.8 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*3.5.0 to before 3.5.8; 3.6.0 to before 3.6.4; 4.0.0 to before 4.0.2VulnerableOpenSSL
  • cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* Versions 3.5.0 to before 3.5.8; 3.6.0 to before 3.6.4; 4.0.0 to before 4.0.2 Vulnerable ·OpenSSL

Remediation

  • Fix · CNA OpenSSL (OpenSSL) Fixed in 4.0.2, 3.6.4, 3.5.8

Red Hat 16 advisories

  • RHSA-2026:95346 Released 2026-11-06 · Red Hat rating Critical
    OpenShift Container Platform 4.22.22 bug fix and security update
    • Red Hat OpenShift Container Platform 4.22 rhcos-aarch64-4.22.9.8.202611032353-0, rhcos-ppc64le-4.22.9.8.202611032353-0, rhcos-s390x-4.22.9.8.202611032353-0 +1
  • RHSA-2026:81201 Released 2026-10-12 · Red Hat rating Important
    Cost Management Metrics Operator Update
    • Cost Management 4 registry.redhat.io/costmanagement/costmanagement-metrics-rhel9-operator
  • 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
Show 13 more Red Hat advisories
  • RHSA-2026:79088 Released 2026-10-08 · Red Hat rating Critical
    Red Hat Developer Hub 1.10.5 release.
    • Red Hat Developer Hub 1.10 registry.redhat.io/rhdh/rhdh-hub-rhel9, registry.redhat.io/rhdh/rhdh-rhel9-operator
  • RHSA-2026:72476 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-operator-rhel9
  • RHSA-2026:72475 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-istio-csr-rhel9
  • RHSA-2026:72470 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/jetstack-cert-manager-acmesolver-rhel9, registry.redhat.io/cert-manager/jetstack-cert-manager-rhel9
  • RHSA-2026:72399 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-operator-rhel9
  • RHSA-2026:72395 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-istio-csr-rhel9
  • RHSA-2026:72394 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/jetstack-cert-manager-rhel9
  • RHSA-2026:71603 Released 2026-09-24 · Red Hat rating Important
    Red Hat Update Infrastructure 5.3 security update
    • Red Hat Update Infrastructure 5 registry.redhat.io/rhui5/cds-kubernetes-rhel9, registry.redhat.io/rhui5/cds-rhel9, registry.redhat.io/rhui5/haproxy-rhel9 +2
  • RHSA-2026:67956 Released 2026-09-16 · Red Hat rating Important
    Red Hat Update Infrastructure 5.3 security update
    • Red Hat Update Infrastructure 5 registry.redhat.io/rhui5/cds-kubernetes-rhel9, registry.redhat.io/rhui5/cds-rhel9, registry.redhat.io/rhui5/haproxy-rhel9 +2
  • RHSA-2026:67165 Released 2026-09-14 · Red Hat rating Important
    openssl security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) openssl-devel-1:3.5.8-1.el9_8, openssl-perl-1:3.5.8-1.el9_8
    • Red Hat Enterprise Linux BaseOS (v. 9) openssl-1:3.5.8-1.el9_8, openssl-libs-1:3.5.8-1.el9_8
  • RHSA-2026:67154 Released 2026-09-14 · Red Hat rating Important
    openssl security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) openssl-devel-1:3.5.8-1.el10_2, openssl-perl-1:3.5.8-1.el10_2
    • Red Hat Enterprise Linux BaseOS (v. 10) openssl-1:3.5.8-1.el10_2, openssl-libs-1:3.5.8-1.el10_2
  • RHSA-2026:59641 Released 2026-08-25 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images openssl-1:3.5.8-0.1.hum1@aarch64, openssl-1:3.5.8-0.1.hum1@src, openssl-1:3.5.8-0.1.hum1@x86_64 +12
  • RHSA-2026:59635 Released 2026-08-25 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images openssl3-1:3.5.8-0.1.hum1@src, openssl3-devel-1:3.5.8-0.1.hum1@aarch64, openssl3-devel-1:3.5.8-0.1.hum1@x86_64 +4

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    OpenSSL — openssl-library.org/news/secadv/20260825.txt

    9 records Highest priority Priority MEDIUM 8 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-45027 Untrusted Sender DN Used as Format String in CMP Response ValidationPriority MEDIUM 51
    • TI-2026-53058 AEAD Forgeries with Empty Ciphertext When Using EVP_Cipher()Priority MEDIUM 47
    • TI-2026-45030 Invalid Pointer Dereference in CMP Server via Crafted protectionAlgPriority MEDIUM 42
    Show all 9 records → Advisory →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat JBoss Core ServicesAffectedNo fix planned: Will not fix
Red Hat JBoss Web Server 6AffectedNo fix planned: Will not fix
Red Hat JBoss Web Server 7AffectedNo fix planned: Will not fix
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Cert Manager support for Red Hat OpenShift release 1.20Fixed RHSA-2026:72394, RHSA-2026:72395, RHSA-2026:72399, RHSA-2026:72470, RHSA-2026:72475, RHSA-2026:72476
Cost Management 4Fixed RHSA-2026:81201
Red Hat Cost Management On-Premise 1Fixed RHSA-2026:79357
Red Hat Developer Hub 1.10Fixed RHSA-2026:79088
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:67154
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:67165
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:67154
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:67165
Red Hat Hardened ImagesFixed RHSA-2026:59635, RHSA-2026:59641
Red Hat OpenShift Container Platform 4.22Fixed RHSA-2026:95346
Red Hat Update Infrastructure 5Fixed RHSA-2026:67956, RHSA-2026:71603
Not affected: 14 products
  • Cert Manager support for Red Hat OpenShift release 1.20
  • Cost Management 4
  • Red Hat Developer Hub 1.10
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat Hardened Images
  • Red Hat OpenShift AI (RHOAI)
  • Red Hat OpenShift Container Platform 4
  • Red Hat Satellite 6
  • Red Hat Satellite Client
  • Red Hat Update Infrastructure 5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-18798
  2. 2026-10-03 Alias added: GHSA-3j55-qf57-hqc2
  3. 2026-10-09 Fix available: RHSA-2026:79088 · Red Hat
  4. 2026-10-09 Fix available: RHSA-2026:79357 · Red Hat
  5. 2026-10-09 Fix available: Red Hat Cost Management On-Premise 1, Red Hat Developer Hub 1.10 · Red Hat
  6. 2026-10-13 Fix available: RHSA-2026:81201 · Red Hat
  7. 2026-10-13 Fix available: Cost Management 4 · Red Hat
  8. 2026-10-21 Affected versions changed · Red Hat
  9. 2026-10-30 Affected versions changed · Red Hat
  10. 2026-11-06 Affected versions changed · Red Hat
  11. 2026-11-07 Fix available: RHSA-2026:95346 · Red Hat
  12. 2026-11-07 Fix available: Red Hat OpenShift Container Platform 4.22 · Red Hat

References

Patch 3

Advisory 1

  • TI-2022-01915 The c_rehash script allows command injection CVSS 3.1CRITICAL 9.8
  • TI-2021-02645 SM2 Decryption Buffer Overflow CVSS 3.1CRITICAL 9.8
  • TI-2009-03392 The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft… CVSS 3.1CRITICAL 9.8
  • TI-2022-01176 The c_rehash script allows command injection CVSS 3.1CRITICAL 9.8
  • TI-2014-00154 The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly… KEVCVSS 3.1HIGH 7.5
  • TI-2025-14107 Stack buffer overflow in CMS (Auth)EnvelopedData parsing CVSS 3.1HIGH 8.8
See all 312 →

Sources

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