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TI-2023-04798 Aliases CVE-2023-5215GHSA-fj2q-5f6j-5xf4

Libnbd: crash or misbehaviour when nbd server returns an unexpected block size

Priority LOW 30CWE-241Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 2 fixed, 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

A flaw was found in libnbd. A server can reply with a block size larger than 2^63 (the NBD spec states the size is a 64-bit unsigned value). This issue could lead to an application crash or other unintended behavior for NBD clients that doesn't treat the return value of the nbd_get_size() function correctly.

Why it matters now

EPSS 0.00806 57th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 1 advisoryRed Hat: 2 fixed, 2 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
Red HatRed Hat Enterprise Linux 9—1.18.1-3.el9Patch availableCNA
Red HatRed Hat Enterprise Linux 8——No fix listedCNA
Red HatRed Hat Enterprise Linux 8 Advanced Virtualization——No fix listedCNA
Red HatRed Hat Enterprise Linux 8 Advanced Virtualization——No fix listedCNA
  • Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in 1.18.1-3.el9 Patch available CNA
  • Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat Enterprise Linux 8 Advanced Virtualization VendorRed Hat Affected — Fixed in — No fix listed CNA
  • Red Hat Enterprise Linux 8 Advanced Virtualization VendorRed Hat Affected — Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:redhat:libnbd:*:*:*:*:*:*:*:*before 1.18.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*8.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*9.0VulnerableRed Hat
  • cpe:2.3:a:redhat:libnbd:*:*:*:*:*:*:*:* Versions before 1.18.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Red Hat

Remediation

Red Hat 1 advisory

  • RHSA-2024:2204 Released 2024-04-30 · Red Hat rating Moderate
    libnbd security update
    • Red Hat Enterprise Linux AppStream (v. 9) libnbd-1.18.1-3.el9, libnbd-bash-completion-1.18.1-3.el9, nbdfuse-1.18.1-3.el9 +1
    • Red Hat Enterprise Linux CRB (v. 9) libnbd-devel-1.18.1-3.el9, ocaml-libnbd-1.18.1-3.el9, ocaml-libnbd-devel-1.18.1-3.el9

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8 Advanced VirtualizationAffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2024:2204
Red Hat Enterprise Linux CRB (v. 9)Fixed RHSA-2024:2204

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-5215
  2. 2026-10-03 Alias added: GHSA-fj2q-5f6j-5xf4

References

Exploit 1

Advisory 3

  • TI-2019-08259 Underflow in PHP-FPM can lead to RCE KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-10530 Code injection in [UNKNOWN] RichFaces KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05975 GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed… KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05157 GNU Bash through 4.3 processes trailing strings after function definitions in the values… KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-23530 Sudo before 1.9.17p1 allows local users to obtain root access because /etc/nsswitch.conf… KEVCVSS 3.1CRITICAL 9.3
  • TI-2021-17490 mod_proxy SSRF KEVCVSS 3.1CRITICAL 9.0
See all 1955 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences