s390/zcrypt: Improve EP11 CPRB length and overflow checks
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Improve EP11 CPRB length and overflow checks The xcrb_msg_to_type6_ep11cprb_msgx() function lacks proper input validation, creating security vulnerabilities: 1. Missing minimum size validation: The ep11_cprb structure and subsequent payload fields (pld_tag, pld_lenfmt) are copied from userspace without verifying sufficient buffer length. 2. Arithmetic overflow in length calculations: CEIL4 alignment could overflow, bypassing size checks and enabling buffer overflows. 3. The payload is asn1 encoded but the function just uses a simple c struct overlay to access some fields of the payload. Fix by using size_t for length calculations, adding U32_MAX boundary checks after alignment, and validating minimum request size and minimum reply size before copying from userspace. Do a very simple asn1 parsing of the payload up to the function value field.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.13
- Fix · CNA Linux (Linux) Fixed in 7.1.10, 7.2
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
Not affected: 5 products
- 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
Timeline
- 2026-10-02 Threatist record created from CVE-2026-80545
- 2026-10-03 Alias added: GHSA-5h39-f843-4g5v
- 2026-10-16 Fix available: Linux/Linux@f463f474773aa49ed1d6087d95d44cea7099fdc7 · CNA
- 2026-10-16 1 new reference · CNA
- 2026-10-21 Fix available: Linux/[email protected] · CNA
References
More Linux vulnerabilities
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- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
Sources
- CVE-2026-80545 · CVE Program
- CVE-2026-80545 · NVD
- FIRST EPSS
- GHSA-5h39-f843-4g5v · GitHub Advisory Database · CC BY 4.0
- CVE-2026-80545 · Red Hat security data · CC BY 4.0
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