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TI-2026-22663 Aliases CVE-2026-28388GHSA-rpg5-467j-c25q

NULL Pointer Dereference When Processing a Delta CRL

Priority MEDIUM 41CWE-476Published · 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: 1 fixed, 8 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

Issue summary: When a delta CRL that contains a Delta CRL Indicator extension is processed a NULL pointer dereference might happen if the required CRL Number extension is missing. Impact summary: A NULL pointer dereference can trigger a crash which leads to a Denial of Service for an application. When CRL processing and delta CRL processing is enabled during X.509 certificate verification, the delta CRL processing does not check whether the CRL Number extension is NULL before dereferencing it. When a malformed delta CRL file is being processed, this parameter can be NULL, causing a NULL pointer dereference. Exploiting this issue requires the X509_V_FLAG_USE_DELTAS flag to be enabled in the verification context, the certificate being verified to contain a freshestCRL extension or the base CRL to have the EXFLAG_FRESHEST flag set, and an attacker to provide a malformed CRL to an application that processes it. The vulnerability is limited to Denial of Service and cannot be escalated to achieve code execution or memory disclosure. For that reason the issue was assessed as Low severity according to our Security Policy. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00919 60th percentileScored 2026-11-07
Fix Partial OpenSSL (OpenSSL): 3.6.2, 3.5.6, 3.4.5 +4Red Hat: 1 advisoryRed Hat: 1 fixed, 8 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
OpenSSLOpenSSL3.6.0 to before 3.6.2; 3.5.0 to before 3.5.6; 3.4.0 to before 3.4.5; 3.3.0 to before 3.3.7; 3.0.0 to before 3.0.20; 1.1.1 to before 1.1.1zg; 1.0.2 to before 1.0.2zp3.6.2, 3.5.6, 3.4.5, 3.3.7, 3.0.20, 1.1.1zg, 1.0.2zpPatch availableCNA
  • OpenSSL VendorOpenSSL Affected 3.6.0 to before 3.6.2; 3.5.0 to before 3.5.6; 3.4.0 to before 3.4.5; 3.3.0 to before 3.3.7; 3.0.0 to before 3.0.20; 1.1.1 to before 1.1.1zg; 1.0.2 to before 1.0.2zp Fixed in 3.6.2, 3.5.6, 3.4.5, 3.3.7, 3.0.20, 1.1.1zg, 1.0.2zp Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*1.0.2 to before 1.0.2zp; 1.1.1 to before 1.1.1zg; 3.0.0 to before 3.0.20; 3.3.0 to before 3.3.7; 3.4.0 to before 3.4.5; 3.5.0 to before 3.5.6; 3.6.0 to before 3.6.2VulnerableOpenSSL
  • cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* Versions 1.0.2 to before 1.0.2zp; 1.1.1 to before 1.1.1zg; 3.0.0 to before 3.0.20; 3.3.0 to before 3.3.7; 3.4.0 to before 3.4.5; 3.5.0 to before 3.5.6; 3.6.0 to before 3.6.2 Vulnerable ·OpenSSL

Remediation

  • Fix · CNA OpenSSL (OpenSSL) Fixed in 3.6.2, 3.5.6, 3.4.5, 3.3.7, 3.0.20, 1.1.1zg, 1.0.2zp

Red Hat 1 advisory

  • RHSA-2026:7261 Released 2026-04-09 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images openssl-3.5.6-0.1.hum1@aarch64, openssl-3.5.6-0.1.hum1@src, openssl-3.5.6-0.1.hum1@x86_64 +10

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/20260407.txt

    7 records Highest priority Priority MEDIUM 6 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-22661 Out-of-bounds Read in AES-CFB-128 on X86-64 with AVX-512 SupportPriority MEDIUM 46
    • TI-2026-24345 Heap Buffer Overflow in Hexadecimal ConversionPriority MEDIUM 42
    • TI-2026-24346 Incorrect Failure Handling in RSA KEM RSASVE EncapsulationPriority MEDIUM 41
    Show all 7 records → Advisory →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat JBoss Core ServicesAffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)Affected—
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat Hardened ImagesFixed RHSA-2026:7261
Not affected: 1 product
  • Red Hat OpenShift AI (RHOAI)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-28388
  2. 2026-10-03 Alias added: GHSA-rpg5-467j-c25q
  3. 2026-11-06 Affected versions changed · Red Hat

References

Patch 5

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