CVE-2026-40355Medium· 5.9▾ TwilightPoC availableIn MIT Kerberos 5 (aka krb5) before 1.22.3, there is a NULL pointer dereference 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 trig…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 32.5 · likelihood 0.1 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Exploit-prediction probability, daily snapshots since Jul 29.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.6%
Exploit / PoC code exists
Last analysed / modified upstream
0.6% → 0.8%
In MIT Kerberos 5 (aka krb5) before 1.22.3, there is a NULL pointer dereference 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, causing the process to terminate in parse_nego_message.
kerberos_5 >= 1.18.0, <= 1.22.2Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-40356Medium· 5.9In 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
CVE-2021-37750Medium· 6.5The Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.18.5 and 1.19.x before 1.19.3 has a NULL pointer dereference in kdc/do_tgs_req.c via a FAST inner body that lacks a server field.
CVE-2021-36222High· 7.5ec_verify in kdc/kdc_preauth_ec.c in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.18.4 and 1.19.x before 1.19.2 allows remote attackers to cause a NULL pointer dereference and daemon crash
CVE-2022-42898High· 8.8PAC parsing in MIT Kerberos 5 (aka krb5) before 1.19.4 and 1.20.x before 1.20.1 has integer overflows that may lead to remote code execution (in KDC, kadmind, or a GSS or Kerberos application server) on 32-bit platforms (which have a res…
CVE-2021-3449Medium· 5.9An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client
CVE-2023-53292Medium· 5.5In the Linux kernel, the following vulnerability has been resolved: blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch_none After grabbing q->sysfs_lock, q->elevator may become NULL because of elevator switch. Fix the NU…