Mongoose: Out-of-bounds Read via length-counter underflow in built-in TLS X.509 DER parser
Mongoose is an embedded web server and network library. Prior to 7.23, the built-in TLS certificate parser selected by MG_TLS_BUILTIN fails to verify that a long-form DER element length fits within the remaining certificate buffer. In mg_der_to_tlv() and mg_der_next(), a peer-controlled length can advance the parser beyond the certificate and underflow the remaining uint32_t length, causing mg_tls_parse_cert_der() to continue walking an invalid pointer. An unauthenticated malicious TLS server, or a client presenting a certificate to a server configured for client certificates, can trigger an out-of-bounds read and denial of service during the handshake. This issue is fixed in version 7.23.
CVE-2026-73260
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-73260
mongoose
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "cesanta",
"product": "mongoose",
"versions": [
{
"status": "affected",
"version": "< 7.23"
}
]
}
]- Related CVEs
- CVE-2026-73260
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #42060 · Revision 1
- Added to Heist Feed
- Publisher date