CVE-2026-23490: pyasn1 has a DoS vulnerability in decoder
(updated )
After reviewing pyasn1 v0.6.1 a Denial-of-Service issue has been found that leads to memory exhaustion from malformed RELATIVE-OID with excessive continuation octets.
References
- github.com/advisories/GHSA-63vm-454h-vhhq
- github.com/pyasn1/pyasn1
- github.com/pyasn1/pyasn1/blob/0f07d7242a78ab4d129b26256d7474f7168cf536/pyasn1/codec/ber/decoder.py
- github.com/pyasn1/pyasn1/commit/3908f144229eed4df24bd569d16e5991ace44970
- github.com/pyasn1/pyasn1/commit/be353d755f42ea36539b4f5053c652ddf56979a6
- github.com/pyasn1/pyasn1/releases/tag/v0.6.2
- github.com/pyasn1/pyasn1/security/advisories/GHSA-63vm-454h-vhhq
- lists.debian.org/debian-lts-announce/2026/02/msg00002.html
- nvd.nist.gov/vuln/detail/CVE-2026-23490
Code Behaviors & Features
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