CVE-2026-61544

CVE-2026-61544 is a high-severity vulnerability with a CVSS 4.0 base score of 8.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-248.

Key facts

Description

libp2p-rust is the official Rust language implementation of the libp2p networking stack. Prior to 0.13.1, libp2p-quic could panic during an inbound QUIC handshake when a remote peer presented a valid short-lived libp2p TLS certificate and delayed the final TLS 1.3 handshake fragment until after the certificate expired. In the Quinn post-handshake upgrade path, transports/quic/src/connection/connecting.rs called libp2p_tls::certificate::parse a second time in remote_peer_id and used expect on the result. The repeated wall-clock validity check could reject the now-expired certificate, causing the expect call to terminate any application exposing an affected libp2p-quic listener. This vulnerability is fixed in 0.13.1.

Frequently asked questions

What is CVE-2026-61544?
libp2p-rust is the official Rust language implementation of the libp2p networking stack. Prior to 0.13.1, libp2p-quic could panic during an inbound QUIC handshake when a remote peer presented a valid short-lived libp2p TLS certificate and delayed the final TLS 1.3 handshake fragment until after the certificate expired. In the Quinn post-handshake upgrade path, transports/quic/src/connection/connecting.rs called libp2p_tls::certificate::parse a second time in remote_peer_id and used expect on the result. The repeated wall-clock validity check could reject the now-expired certificate, causing the expect call to terminate any application exposing an affected libp2p-quic listener. This vulnerability is fixed in 0.13.1.
How severe is CVE-2026-61544?
CVE-2026-61544 has a CVSS 4.0 base score of 8.2, rated high severity.
Is CVE-2026-61544 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-61544?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-61544 published?
CVE-2026-61544 was published on 2026-09-15 and last updated on 2026-09-30.

References

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