CVE-2026-119196 pyasn1 - Denial of Service

pyasn1 < 0.6.5 contains a denial of service caused by quadratic CPU exhaustion during constructed BIT STRING decoding with attacker-controlled fragmented input, letting attackers exhaust CPU resources, exploit requires crafted BER or CER input.

CVSS base score 7.5 /10
High
CISA KEV
Not listed
Public exploit
None known
Authentication
Not required
EPSS
0.43% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Denial of Service
Impact
Denial Of Service
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
29 October 2026
Updated
31 October 2026
Weakness
CWE-407

Vendor fix

Update to version 0.6.5 or later.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

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