Security readout for executives and security teams
Plain-English summary
CVE-2025-6395 is a GnuTLS crash-class flaw caused by a NULL pointer dereference during cipher suite negotiation. For affected systems, the main business risk is service disruption, not data theft. Red Hat lists multiple RHEL, OpenShift, Ceph, Discovery, and Insights proxy products as affected.
Executive priority
Treat as a moderate operational resilience issue. It deserves timely patch management, especially for exposed TLS services, but the supplied evidence does not support emergency active-exploitation handling.
Technical view
The flaw is in _gnutls_figure_common_ciphersuite() in GnuTLS and is classified as CWE-476. CVSS 3.1 is 6.5 with network access, no privileges, no user interaction, high attack complexity, low integrity impact, and high availability impact.
Likely exposure
Exposure is most likely on systems or containers using affected Red Hat gnutls/libgnutls packages in RHEL 8, 9, 10, OpenShift 4, Ceph Storage 7, Discovery 2, or Insights proxy. RHEL 6 and 7 status is listed as unknown in the supplied data.
Exploitation context
The source bundle does not show KEV listing or cited active exploitation. The CVSS vector indicates remote reachability without authentication or user interaction, but high attack complexity. Available evidence supports a potential denial-of-service or crash scenario, with limited integrity impact and no stated confidentiality impact.
Researcher notes
Evidence is strongest for Red Hat-tracked affected products and package names. The bundle names the vulnerable function and CWE but does not provide root-cause detail, exploit proof, or universal upstream fixed versions. Avoid expanding affected scope beyond cited products without vendor confirmation.
Mitigation direction
- Apply relevant Red Hat security advisories for affected products after vendor review.
- Prioritize internet-facing TLS services using GnuTLS-backed components.
- Check vendor guidance for products with unknown or downstream package status.
- Update affected containers or base images that include vulnerable gnutls packages.
- Monitor Red Hat, GnuTLS, Debian, and Siemens advisories for revised guidance.
Validation and detection
- Inventory installed gnutls/libgnutls package versions across Linux hosts and containers.
- Map findings to affected Red Hat product entries and RHSA advisories.
- Confirm OpenShift nodes and images inherit updated RHCOS or package content.
- Review service logs for abnormal TLS negotiation crashes or restarts.
- Track RHEL 6 and 7 separately because status is listed as unknown.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-476: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupContainer behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2025-6395 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H2.24.2redhatVulnerability scoring details
Base CVSS 3.1 score
6.5MediumVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineredhat
Reported to Red Hat.
- Source timelineredhat
Made public.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- RHSA-2025:16115CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:16116CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:17181CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:17348CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:17361CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:17415CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:19088CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:22529CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2025-6395CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2376755CVE reference, redhat · issue-tracking, x_refsource_REDHAT
- https://gitlab.com/gnutls/gnutls/-/issues/1718CVE reference, redhat
- https://lists.gnupg.org/pipermail/gnutls-help/2025-July/004883.htmlCVE reference, redhat
- https://lists.debian.org/debian-lts-announce/2025/08/msg00005.htmlCVE reference, CVE
- https://cert-portal.siemens.com/productcert/html/ssa-082556.htmlCVE reference, siemens-SADP
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
NULL Pointer Dereference
NULL Pointer Dereference represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.