CVE-2023-6915 — Kernel: null pointer dereference vulnerability in ida_free in lib/idr.c

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

• Documented patch — github.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

1. Identify exposed assets running the affected vendor/product/version combinations (Debian Debian Linux, Linux Linux Kernel, Red Hat Codeready Linux Builder…).
2. Apply the fixed version or the patch documented under Remediation.
3. Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-476 · NULL Pointer Dereference

Other CVEs with this weakness →

EPSS over time FIRST

Oct 22, 2026 → Oct 23, 2026 · 2 reading(s) · max 0.26%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

• Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
• Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.

Timeline

What happened to this CVE, newest first.

• 2026
• Affected products added · red hat/red hat enterprise linux 8, red hat/red hat enterprise linux 9
  Oct 23, 2026 · CVE Program (cve.org) e CISA ADP
• SSVC assessment updated
  Oct 23, 2026 · CVE Program (cve.org) e CISA ADP
• Record published
  Oct 23, 2026
• Fix documented
  Oct 23, 2026 · NIST National Vulnerability Database
• Affected products added · debian/debian linux, redhat/codeready linux builder, redhat/codeready linux builder for arm64, redhat/codeready linux bu
  Oct 23, 2026 · NIST National Vulnerability Database
• CVSS changed · 5.5
  Oct 23, 2026 · NIST National Vulnerability Database
• Source status changed · → Analyzed
  Oct 23, 2026 · NIST National Vulnerability Database
• Record created in this database
  Oct 23, 2026 · Alertas do Telegram
• 2024
• CVE published
  Jan 15, 2024 · redhat

Source activity

Repeated readings are counted rather than listed.

• 2× References added · Oct 23, 2026 – Oct 23, 2026
• 1× Official description updated · Oct 23, 2026 – Oct 23, 2026

References

9 on the record

• access.redhat.com/errata/RHSA-2024:3138
  Vendor Advisory, vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• access.redhat.com/errata/RHSA-2024:2394
  Vendor Advisory, vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• access.redhat.com/errata/RHSA-2024:2950
  Vendor Advisory, vendor-advisory, x_refsource_REDHAT, NIST National Vulnerability Database
• github.com/torvalds/linux/commit/af73483f4e8b6f5c68c9aa63257bdd929a9c194a
  Patch, NIST National Vulnerability Database
• access.redhat.com/security/cve/CVE-2023-6915
  Third Party Advisory, vdb-entry, x_refsource_REDHAT, NIST National Vulnerability Database
• lists.debian.org/debian-lts-announce/2024/06/msg00016.html
  Mailing List, Third Party Advisory, NIST National Vulnerability Database
• bugzilla.redhat.com/show_bug.cgi
  Issue Tracking, issue-tracking, x_refsource_REDHAT, NIST National Vulnerability Database
• github.com/advisories/GHSA-3cfm-49vw-5qrv
  GitHub Security Advisories
• nvd.nist.gov/vuln/detail/CVE-2023-6915
  GitHub Security Advisories

Elsewhere on this site

Related CVEs (same products)

• High CVE-2026-115484 Open-iscsi: open-iscsi: dhcpv4 option parser heap out-of-bounds read in iscsiuio parse_msg 1d
• High CVE-2026-115486 Open-iscsi: open-iscsi: ipv6 neighbor discovery missing option length validation in iscsiuio allows arp table poisoning 1d
• Medium CVE-2026-115485 Open-iscsi: open-iscsi: dhcpv6 vendor option strlen heap out-of-bounds read and 1-byte write in iscsiuio 1d
• Low CVE-2026-115449 Libslirp: libslirp: icmp echo reply length desynchronization leaks host ip to guest 1d
• Medium CVE-2026-115221 Ipa: freeipa: freeipa uses subject cn as proof of certificate ownership 1d
• Medium CVE-2026-115207 Patch: filename validation bypass in reversal fallback allows file creation outside the working directory 2d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

• No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
• No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
• No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2023-6915 is "Kernel: null pointer dereference vulnerability in ida_free in lib/idr.c", rated Medium. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.26% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.

Sign in or create an account to comment and suggest corrections.