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TI-2026-45029 Aliases CVE-2026-63075GHSA-cj75-r57j-r5v8

QUIC ACK-only Packet Retention Can Cause Memory Exhaustion

Priority MEDIUM 40CWE-770Published · 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: 7 fixed, 7 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-770.

Summary

Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer, potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is outside the FIPS module boundary.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0057 47th percentileScored 2026-11-07
Fix Partial OpenSSL (OpenSSL): 4.0.2, 3.6.4, 3.5.8 +1Red Hat: 12 advisoriesRed Hat: 7 fixed, 7 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 3.5.8; 3.4.0 to before 3.4.74.0.2, 3.6.4, 3.5.8, 3.4.7Patch 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; 3.4.0 to before 3.4.7 Fixed in 4.0.2, 3.6.4, 3.5.8, 3.4.7 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*3.4.0 to before 3.4.7; 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 3.4.0 to before 3.4.7; 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, 3.4.7

Red Hat 12 advisories

  • 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
Show 9 more Red Hat advisories
  • 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: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Developer Hub 1AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat JBoss Core ServicesAffectedNo fix yet: Fix deferred
Red Hat JBoss Web Server 6AffectedNo fix yet: Fix deferred
Red Hat JBoss Web Server 7AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred
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
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 Update Infrastructure 5Fixed RHSA-2026:67956, RHSA-2026:71603
Not affected: 12 products
  • Cert Manager support for Red Hat OpenShift release 1.20
  • 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-2026-63075
  2. 2026-10-03 Alias added: GHSA-cj75-r57j-r5v8
  3. 2026-10-23 EPSS moved to the below the 50th percentile
  4. 2026-10-27 Affected versions changed · Red Hat
  5. 2026-10-30 Affected versions changed · Red Hat
  6. 2026-11-07 Affected versions changed · Red Hat

References

Patch 4

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