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TI-2021-12953 Aliases CVE-2021-33560GHSA-g9p5-p7h5-p2wg

Libgcrypt before 1.8.8 and 1.9.x before 1.9.3 mishandles ElGamal encryption because it…

Priority MEDIUM 43CWE-325Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Partial Red Hat: 1 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-203.

Summary

Libgcrypt before 1.8.8 and 1.9.x before 1.9.3 mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm, and the window size is not chosen appropriately. This, for example, affects use of ElGamal in OpenPGP.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0237 83rd percentileScored 2026-11-07
Fix Partial Red Hat: 1 advisoryRed Hat: 1 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 12

CPEVersionsRoleVendor
cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:*before 1.8.8; 1.9.0 to before 1.9.3VulnerableGnuPG
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*33VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*34VulnerableFedoraproject
cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:1.11.0:*:*:*:*:*:*:*1.11.0VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:1.9.0:*:*:*:*:*:*:*1.9.0VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:1.10.0:*:*:*:*:*:*:*1.10.0VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_network_repository_function:1.14.0:*:*:*:*:*:*:*1.14.0VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_network_repository_function:1.15.0:*:*:*:*:*:*:*1.15.0VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_network_repository_function:1.15.1:*:*:*:*:*:*:*1.15.1VulnerableOracle
  • cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:* Versions before 1.8.8; 1.9.0 to before 1.9.3 Vulnerable ·GnuPG
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
  • cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject
  • cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:1.11.0:*:*:*:*:*:*:* Versions 1.11.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:1.9.0:*:*:*:*:*:*:* Versions 1.9.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:1.10.0:*:*:*:*:*:*:* Versions 1.10.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_network_repository_function:1.14.0:*:*:*:*:*:*:* Versions 1.14.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_network_repository_function:1.15.0:*:*:*:*:*:*:* Versions 1.15.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_network_repository_function:1.15.1:*:*:*:*:*:*:* Versions 1.15.1 Vulnerable ·Oracle
Show 2 more CPE
CPEVersionsRoleVendor
cpe:2.3:a:oracle:communications_cloud_native_core_network_slice_selection_function:1.8.0:*:*:*:*:*:*:*1.8.0VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_service_communication_proxy:1.15.0:*:*:*:*:*:*:*1.15.0VulnerableOracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_network_slice_selection_function:1.8.0:*:*:*:*:*:*:* Versions 1.8.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_service_communication_proxy:1.15.0:*:*:*:*:*:*:* Versions 1.15.0 Vulnerable ·Oracle

Remediation

Red Hat 1 advisory

  • RHSA-2021:4409 Released 2021-11-09 · Red Hat rating Moderate
    libgcrypt security and bug fix update
    • Red Hat Enterprise Linux BaseOS (v. 8) libgcrypt-1.8.5-6.el8, libgcrypt-devel-1.8.5-6.el8

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2021:4409
Not affected: 1 product
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-33560
  2. 2026-10-03 Alias added: GHSA-g9p5-p7h5-p2wg

References

Patch 4

Advisory 8

Sources

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