CVE-2021-3580

Public on

Last Modified: UTC

Description

A flaw was found in nettle in the way its RSA decryption functions handle specially crafted ciphertext. This flaw allows an attacker to provide a manipulated ciphertext, leading to an application crash and a denial of service.

A flaw was found in nettle in the way its RSA decryption functions handle specially crafted ciphertext. This flaw allows an attacker to provide a manipulated ciphertext, leading to an application crash and a denial of service.

Mitigation

As per upstream: For applications that want to support older versions of nettle, the bug can be worked around by adding a check that the RSA ciphertext is in the range 0 < ciphertext < n, before attempting to decrypt it.

Additional information

  • Bugzilla 1967983: nettle: Remote crash in RSA decryption via manipulated ciphertext
  • CWE-20: Improper Input Validation
  • FAQ: Frequently asked questions about CVE-2021-3580

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown
Red HatNVD

CVSS v3 Base Score

7.5

7.5

Attack Vector

Network

Network

Attack Complexity

Low

Low

Privileges Required

None

None

User Interaction

None

None

Scope

Unchanged

Unchanged

Confidentiality Impact

None

None

Integrity Impact

None

None

Availability Impact

High

High

CVSS v3 Vector

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

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

Acknowledgements

Red Hat would like to thank the GNU Nettle project for reporting this issue.

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?

What can I do if my product is listed as "Will not fix"?

What can I do if my product is listed as "Fix deferred"?

What is a mitigation?

I have a Red Hat product but it is not in the above list, is it affected?

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

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