Answer in brief
CVE-2026-119196 records a High severity (CVSS 7.5) vulnerability in pyasn1: Quadratic CPU consumption in constructed BIT STRING decoding. The current sources do not mark it as known exploited. The current feed maps pyasn1/pyasn1 (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps pyasn1/pyasn1 (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| pyasn1/pyasn1generic | <0.6.5 | 0.6.5 |
Published upstream
Oct 29, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 29, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 29, 2026
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.5, constructed BIT STRING decoding repeatedly shifts and copies the complete bit value accumulated from earlier fragments. Attacker-controlled BER or CER input contains many constructed BIT STRING fragments; schema-driven DER also accepts a definite-length constructed BIT STRING. BitStringPayloadDecoder repeatedly calls BitString.fromOctetString with the prior bitString as prepend, shifting an ever-growing SizedInteger for each fragment and causing quadratic work. Large fragmented values can exhaust CPU during decode() without requiring later conversion or formatting. This issue is fixed in version 0.6.5.
Quoted source text, attributed separately from HOL analysis.