CVE-2026-18798
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QUIC Server May Trigger Double Free When Processing INITIAL Packet
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Hindsight · the state
Foresight · where to check next
This record is one instance of CWE-415, double free. The index holds 885 prior instances of this class, 6 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1
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Current rung: Nothing observed in held sources.
- RUNG 1Nothing observed in held sources
- RUNG 2Proof-of-concept published
- RUNG 3Exploited in the wild · CISA KEV listed
- RUNG 4Ransomware campaign use known
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What it is stated by the CNA
Issue summary: QUIC server may double free QRX (QUIC record layer RX) object when channel creation fails for initial packet. Impact summary: Double free leads to heap corruption, which typically results in termination of QUIC server process, leading to Denial of Service. There is so far no evidence that this double free is exploitable for remote code execution, thus it is considered highly improbable. CWE: CWE-415: Double Free Description: In order to validate initial packet, OpenSSL QUIC stack default packet handler (port_default_packet_handler()) creates a so-called QRX object. If the initial packet validates successfully with QRX object, the default packet handler proceeds to channel receipt
Read the rest of the CNA's description
(connection object) creation. The QRX object used for packet validation is passed to port_bind_channel(), so it becomes part of the newly created connection. If port_bind_channel() fails, then it also frees the QRX object. Once port_bind_channel() returns, the port_default_packet_handler() detects the failure and proceeds to the error branch, where the same QRX object is freed for the second time. The failure in port_bind_channel() function can be induced with a relatively low effort by a malformed (non RFC 9000 compliant) INITIAL packet. If the packet carries DCID (destination connection ID) which is shorter than 8 bytes, then port_bind_channel() jumps to the error path after ossl_quic_lcidm_enrol_odcid() detects that the DCID has invalid length. FIPS impact: no The FIPS module is not affected, as the QUIC implementation is outside of the OpenSSL FIPS module boundary.
NVD's analysis a second authority
- weakness
- CWE-415
- also scored by
- 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
check it yourself openssl-library.org github.com github.com github.com receipt
Movement
Only one observation of this value is held, so there is no movement to show yet.
The full biography
The record had been public for 3 days when this index was last written.
The pattern, elsewhere
This record is one instance of CWE-415, double free. The index holds 885 prior instances of this class, 6 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]
"Matches n of m" counts the attributes the two records can both be compared on: the CVSS metrics they share a version of, any weakness class beyond this one, and the vendor. fit-rules@v1
885 records in this class held. The six above are drawn from the ones CISA has listed as exploited, ranked by how much of the record matches this one. That is why every one of them is KEV-listed: the pool is, so the colour on those spokes says nothing the pool has not already said.
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Siblings and hubs
Records related to this one
No record cites this identifier and it carries no alias. Its defect family is below.
Its defect family
openssl
Of the 3 records in this family, this is the only one holding a stated fix version: 4.0.2; 3.6.4; 3.5.8.
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What usually comes next
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