CyberSecBulletin
CVE-2026-42010NVD status: Modified

Red Hat Enterprise Linux 10: Improper Null Termination

CVE-2026-42010 is a critical-severity improper null termination vulnerability in Red Hat Enterprise Linux 10 from Red Hat, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 1.05% chance of exploitation within 30 days, higher than 65% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Red Hat Enterprise Linux 10 you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on access.redhat.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Red HatRed Hat Enterprise Linux 10Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 10.0 Extended Update SupportNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-OnNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update SupportNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-OnNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update ServiceNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP SolutionsNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 9Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 9.2 Update Services for SAP SolutionsNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 9.4 Update Services for SAP SolutionsNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 9.6 Extended Update SupportNot specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.12Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.13Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.14Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.15Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.16Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.17Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.18Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.19Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.20Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.21Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.22Not specified in the recordNot stated
Red HatCert Manager support for Red Hat OpenShift release 1.17Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE; 15 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.1HighCNA (redhat.com)
CVSS 3.19.8CriticalNVD
CVSS 3.17.1HighCNA

Official description

A flaw was found in gnutls. Servers configured with RSA-PSK (Rivest–Shamir–Adleman – Pre-Shared Key) wrongfully matched usernames containing a NUL character with truncated usernames. A remote attacker could exploit this by sending a specially crafted username, leading to an authentication bypass. This vulnerability allows an attacker to gain unauthorized access by circumventing the authentication process.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Null Termination

The product does not terminate or incorrectly terminates a string or array with a null character or equivalent terminator.

How developers prevent this class of flaw

  • Use a language that is not susceptible to these issues. However, be careful of null byte interaction errors (CWE-626) with lower-level constructs that may be written in a language that is susceptible.
  • Ensure that all string functions used are understood fully as to how they append null characters. Also, be wary of off-by-one errors when appending nulls to the end of strings.
  • If performance constraints permit, special code can be added that validates null-termination of string buffers, this is a rather naive and error-prone solution.

More Improper Null Termination vulnerabilities (CWE-170)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Red Hat Enterprise Linux 10

All Red Hat Enterprise Linux 10 vulnerabilities

Recent Improper Null Termination vulnerabilities

Spotted an error? Tell us.