CVE-2026-119194
pyasn1 is a generic ASN.1 library for Python
- Risk score
- 60/100
- CVSS
- 7.5 v3.1
- Published
- 29 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- pyasn1 is a generic ASN.1 library for Python. From 0.3.3 until 0.6.5, schemaless container decoding stores every decoded component's TagSet in a growing set even though only one-versus-multiple tag types must be distinguished. Attacker-controlled BER, CER, or DER input contains many distinct long tag IDs whose TagSet …
- Affected
- See advisory
- Fix
- Upgrade the product to 0.6.5 or later.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 7.5 high
- Remotely exploitable without logging in
- On your watchlist: python
References
Original description
pyasn1 is a generic ASN.1 library for Python. From 0.3.3 until 0.6.5, schemaless container decoding stores every decoded component's TagSet in a growing set even though only one-versus-multiple tag types must be distinguished. Attacker-controlled BER, CER, or DER input contains many distinct long tag IDs whose TagSet hashes collide. Each later set insertion compares against an increasing number of earlier colliding tags in ConstructedPayloadDecoderBase._decodeComponentsSchemaless, producing quadratic CPU work while decoded values and order remain valid. Repeated inputs can exhaust decoder CPU and reduce service availability. This issue is fixed in version 0.6.5.
Last activity 29 Oct 2026. Patch Forecast updates every hour.