CVE-2021-40528

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

1.42% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 71.0% of scored records. A rank, not a probability.

NVD base score

5.9 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-09-06 00:00Z4 YR AGO

Last updated

2025-06-09 15:13Z1 YR AGO

Reserved

2021-09-06

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Medium (CVSS 5.9)

CNA CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Weaknesses

• CWE-327Use of a Broken or Risky Cryptographic AlgorithmClass

Data version

5.1

Document digest

9a055a9b0a8401a7d7ed90caa2d421e4e1842ab6ebcd0c4cab9690272a521842

• eprint.iacr.orghttps://eprint.iacr.org/2021/923
• ibm.github.iohttps://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1
• ibm.github.iohttps://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2
• git.gnupg.orghttps://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=3462280f2e23e16adf3ed5176e0f2413d8861320
• security.gentoo.orgGLSA-202210-13https://security.gentoo.org/glsa/202210-13vendor-advisory