CVE-2026-89539
Last modified
CVE-2026-89539 is a vulnerability of currently unknown severity. In the Linux kernel, the following vulnerability has been resolved: SUNRPC: reject duplicate CREDS_VALUE options gssx_dec_option_array() walks the wire-supplied option array and, for every entry whose name matches CREDS_VALUE, calls gssx_dec_linux_creds() on the same struct svc_cred. That helper unconditionally installs a fresh groups_alloc() result into creds->cr_group_info without releasing whatever pointer was already there: for (i = 0; i < count; i++) { ...
Description
In the Linux kernel, the following vulnerability has been resolved: SUNRPC: reject duplicate CREDS_VALUE options gssx_dec_option_array() walks the wire-supplied option array and, for every entry whose name matches CREDS_VALUE, calls gssx_dec_linux_creds() on the same struct svc_cred. That helper unconditionally installs a fresh groups_alloc() result into creds->cr_group_info without releasing whatever pointer was already there: for (i = 0; i < count; i++) { ... decode name ... if (length == sizeof(CREDS_VALUE) && memcmp(p, CREDS_VALUE, sizeof(CREDS_VALUE)) == 0) { err = gssx_dec_linux_creds(xdr, creds); ... } } A reply that carries two CREDS_VALUE entries therefore overwrites cr_group_info on the second iteration and orphans the group_info allocated by the first call. The earlier free_creds path only releases the last cr_group_info via free_svc_cred(), so the first allocation's refcount stays at one and its kvmalloc-backed storage is leaked. No in-tree caller of gssp_accept_sec_context_upcall() expects more than one CREDS_VALUE per reply. Fix by tracking whether a CREDS_VALUE option has already been decoded and returning -EINVAL on any subsequent match, so the free_creds path releases the single group_info that was installed.
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 1d658336b05f8697d6445834f8867f8ad5e4f735, < f615b884310bf82d0014e3b5a92eb9aa88146685; >= 1d658336b05f8697d6445834f8867f8ad5e4f735, < 7a1d0501cbb962beba23377035d667bf3c1726ee; >= 1d658336b05f8697d6445834f8867f8ad5e4f735, < 9d94f046b23de0f77849ea69133063c949297e30; >= 1d658336b05f8697d6445834f8867f8ad5e4f735, < 2e4ce62385c1b8a887c5370af058ac7b52a8eaf9 |
| Linux | Linux | 3.10 |
References
Timeline
- Published
- Last Modified
- Status
- Received
Frequently Asked Questions
What is CVE-2026-89539?
How severe is CVE-2026-89539?
How do I fix CVE-2026-89539?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-89533In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89534In the Linux kernel, the following vulnerability has been re…8.8
- CVE-2026-89535In the Linux kernel, the following vulnerability has been re…8.1
- CVE-2026-89536In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89537In the Linux kernel, the following vulnerability has been re…9.1
- CVE-2026-89538In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-8954Incorrect boundary conditions, integer overflow in the Audio…7.5
- CVE-2026-89540In the Linux kernel, the following vulnerability has been re…7.8
- CVE-2026-89541In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89542In the Linux kernel, the following vulnerability has been re…9.8
- CVE-2026-89543In the Linux kernel, the following vulnerability has been re…
- CVE-2026-89544In the Linux kernel, the following vulnerability has been re…7.5
Are you affected by CVE-2026-89539?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
