This page tracks the Ubuntu fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-59886 →

UBUNTU-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 us...

Original description

The description as published by the source.

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.

Source: OSV.dev (Open Source Vulnerabilities) OSV

Affected packages

Ubuntu:Pro:14.04:LTS pyasn1

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Ubuntu:Pro:16.04:LTS pyasn1

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Ubuntu:Pro:18.04:LTS pyasn1

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Ubuntu:Pro:20.04:LTS pyasn1

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Ubuntu:22.04:LTS pyasn1

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.8-1ubuntu0.3"}]}]

Ubuntu:24.04:LTS pyasn1

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.8-4ubuntu0.3"}]}]

Ubuntu:26.04:LTS pyasn1

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.6.3-1ubuntu0.1"}]}]

References

advisory ubuntu.com
report ubuntu.com
report cve.org
report github.com
report github.com