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TI-2021-02650 Aliases CVE-2021-3716GHSA-3vpg-mwgf-4jvj

A flaw was found in nbdkit due to to improperly caching plaintext state across the…

Priority LOW 16CWE-924Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
None · None · Low
Fix status
Partial Red Hat: 3 fixed, 1 without a fix

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

Summary

A flaw was found in nbdkit due to to improperly caching plaintext state across the STARTTLS encryption boundary. A MitM attacker could use this flaw to inject a plaintext NBD_OPT_STRUCTURED_REPLY before proxying everything else a client sends to the server, potentially leading the client to terminate the NBD session. The highest threat from this vulnerability is to system availability.

Why it matters now

EPSS 0.00582 48th percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 3 fixed, 1 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
—nbdkitAffects nbdkit v1.12 through v1.26.4 | Fixedin nbdkit v1.26.5—No fix listedCNA
  • nbdkit Vendor— Affected Affects nbdkit v1.12 through v1.26.4 | Fixedin nbdkit v1.26.5 Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:nbdkit_project:nbdkit:*:*:*:*:*:*:*:*1.11.8 to before 1.24.6; 1.25.1 to before 1.26.5; 1.27.1 to before 1.27.6VulnerableNbdkit Project
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:-:*:*:*8.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:advanced_virtualization:*:*:*8.0VulnerableRed Hat
  • cpe:2.3:a:nbdkit_project:nbdkit:*:*:*:*:*:*:*:* Versions 1.11.8 to before 1.24.6; 1.25.1 to before 1.26.5; 1.27.1 to before 1.27.6 Vulnerable ·Nbdkit Project
  • cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:-:*:*:* Versions 8.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:advanced_virtualization:*:*:* Versions 8.0 Vulnerable ·Red Hat

Remediation

Red Hat 2 advisories

  • RHSA-2022:1759 Released 2022-05-10 · Red Hat rating Moderate
    virt:rhel and virt-devel:rhel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 8) SLOF-20210217-1.module+el8.6.0+14480+c0a3aa0f.noarch::virt:rhel, SLOF-20210217-1.module+el8.6.0+14480+c0a3aa0f.src::virt:rhel, hivex-1.3.18-23.module+el8.6.0+14480+c0a3aa0f.aarch64::virt:rhel +47
    • Red Hat Enterprise Linux CRB (v. 8) SLOF-20210217-1.module+el8.6.0+14480+c0a3aa0f.src::virt-devel:rhel, hivex-1.3.18-23.module+el8.6.0+14480+c0a3aa0f.i686::virt-devel:rhel, hivex-devel-1.3.18-23.module+el8.6.0+14480+c0a3aa0f.i686::virt-devel:rhel +47
  • RHSA-2022:0397 Released 2022-02-02 · Red Hat rating Low
    virt:av and virt-devel:av security and bug fix update
    • Advanced Virtualization for RHEL 8.5.0.Z SLOF-20210217-1.module+el8.5.0+10946+35bb3930.noarch::virt:av, SLOF-20210217-1.module+el8.5.0+10946+35bb3930.src::virt-devel:av, SLOF-20210217-1.module+el8.5.0+10946+35bb3930.src::virt:av +47

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 8 Advanced VirtualizationAffectedNo fix yet
Advanced Virtualization for RHEL 8.5.0.ZFixed RHSA-2022:0397
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2022:1759
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2022:1759
Not affected: 3 products
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 9
  • Red Hat Virtualization 4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-3716
  2. 2026-10-03 Alias added: GHSA-3vpg-mwgf-4jvj

References

Patch 3

Advisory 1

Other 1

Sources

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