CVE-2026-40356_CVE-2026-40356

5.9 / 10

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

In MIT Kerberos 5 (aka krb5) before 1.22.3, there is an integer underflow and resultant out-of-bounds read if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, possibly causing the process to terminate in parse_message.

Basic Information

ID CVE-2026-40356

Source mitre

Published Apr 28, 2026 at 00:00

Modified Apr 28, 2026 at 05:23

Affected Product

Vendor MIT

Product Kerberos 5

Version 1.18

Affected Versions MIT Kerberos 5 1.18

CWE Classification

CWE-191

References

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    "published": "2026-04-28T00:00:00.000Z",
    "modified": "2026-04-28T05:23:13.610Z",
    "type": "cve",
    "title": "CVE-2026-40356",
    "source": "mitre",
    "references": "https://web.mit.edu/kerberos/advisories/\nhttps://cems.fun/2026/04/27/krb5-two-unauthenticated-network-vulnerabilities.html\nhttps://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f",
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