CVE-2026-59886

pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the univ.Real type converted its mantissa, base, and exponent value to a Python float using exact big-integer exponentiation. A BER, CER, or DER encoded REAL value only a few bytes long can carry a very large exponent, causing float conversion through prettyPrint(), str(), comparison, arithmetic, int(), or an explicit float() call to consume excessive CPU and memory and hang applications that decode untrusted ASN.1 data and then print, log, or compare decoded objects. This issue is fixed in version 0.6.4.
Configurations

Configuration 1 (hide)

cpe:2.3:a:pyasn1:pyasn1:*:*:*:*:*:python:*:*

History

21 Jul 2026, 14:38

Type Values Removed Values Added
References () https://github.com/pyasn1/pyasn1/commit/e60c691cb91addb8fcefa2f537e85ede6fb1e886 - () https://github.com/pyasn1/pyasn1/commit/e60c691cb91addb8fcefa2f537e85ede6fb1e886 - Patch
References () https://github.com/pyasn1/pyasn1/releases/tag/v0.6.4 - () https://github.com/pyasn1/pyasn1/releases/tag/v0.6.4 - Release Notes
References () https://github.com/pyasn1/pyasn1/security/advisories/GHSA-hm4w-wwcw-mr6r - () https://github.com/pyasn1/pyasn1/security/advisories/GHSA-hm4w-wwcw-mr6r - Third Party Advisory
First Time Pyasn1
Pyasn1 pyasn1
CPE cpe:2.3:a:pyasn1:pyasn1:*:*:*:*:*:python:*:*

14 Jul 2026, 17:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-07-14 17:17

Updated : 2026-07-21 14:38


NVD link : CVE-2026-59886

Mitre link : CVE-2026-59886

CVE.ORG link : CVE-2026-59886


JSON object : View

Products Affected

pyasn1

  • pyasn1
CWE
CWE-400

Uncontrolled Resource Consumption

CWE-770

Allocation of Resources Without Limits or Throttling