CVE-2026-42009
HighCVSS 7.5Exploitation Probability (EPSS)
Elevated risk69th percentile - higher than 69% of all known CVEs
Summary
A flaw was found in GnuTLS in the DTLS packet reordering logic. The comparator function does not correctly handle packets with duplicate sequence numbers, leading to unstable ordering or undefined behavior, resulting in a denial of service.
Risk Assessment
A remote attacker can cause a denial of service in applications using GnuTLS with DTLS, disrupting time-sensitive communications.
Recommendation
Update the GnuTLS library to a version that fixes the handling of duplicate DTLS sequence numbers.
Other vulnerabilities in GnuTLS
See all- CVE-2016-4456High
The 'GNUTLS_KEYLOGFILE' environment variable in gnutls 3.4.12 allows remote attackers to overwrite and corrupt arbitrary files in the filesystem.
- CVE-2017-7507High
GnuTLS version 3.5.12 and earlier is vulnerable to a NULL pointer dereference while decoding a status response TLS extension with valid contents. This could lead to a crash of the GnuTLS server application.
- CVE-2017-7869High
GnuTLS before February 20, 2017, has an out-of-bounds write caused by an integer overflow and heap-based buffer overflow related to the cdk_pkt_read function in opencdk/read-packet.c. This issue is a subset of the vendor's GNUTLS-SA-2017-3 report and is fixed in version 3.5.10.
- CVE-2017-5335High
The stream reading functions in lib/opencdk/read-packet.c in GnuTLS before 3.3.26 and 3.5.x before 3.5.8 allow remote attackers to cause a denial of service (out-of-memory error and crash) via a crafted OpenPGP certificate.
- CVE-2016-7444High
The gnutls_ocsp_resp_check_crt function in GnuTLS before 3.4.15 and 3.5.x before 3.5.4 does not verify the serial length of an OCSP response, which might allow remote attackers to bypass an intended certificate validation mechanism.
- CVE-2015-3308High
A double free vulnerability in lib/x509/x509_ext.c in GnuTLS before version 3.3.14 allows remote attackers to cause a denial of service or possibly have unspecified other impact via a crafted CRL distribution point.
- CVE-2024-28834Medium
A flaw was found in GnuTLS related to the Minerva attack, a cryptographic vulnerability that exploits deterministic behavior, leading to side-channel leaks. In specific scenarios, such as using the GNUTLS_PRIVKEY_FLAG_REPRODUCIBLE flag, it can result in a noticeable step in nonce values.
- CVE-2017-5337Critical
Multiple heap-based buffer overflows in the read_attribute function in GnuTLS before 3.3.26 and 3.5.x before 3.5.8 allow remote attackers to have unspecified impact via a crafted OpenPGP certificate.
- CVE-2017-5336Critical
A stack-based buffer overflow in the cdk_pk_get_keyid function in lib/opencdk/pubkey.c in GnuTLS before 3.3.26 and 3.5.x before 3.5.8 allows remote attackers to have unspecified impact via a crafted OpenPGP certificate.
- CVE-2017-5334Critical
A double free vulnerability in the gnutls_x509_ext_import_proxy function in GnuTLS before 3.3.26 and 3.5.x before 3.5.8 allows remote attackers to have unspecified impact via crafted policy language information in an X.509 certificate with a Proxy Certificate Information extension.
Original NVD description (English source)
A flaw was found in gnutls. A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic. The comparator function, responsible for ordering DTLS packets by sequence numbers, did not correctly handle packets with duplicate sequence numbers. This could lead to unstable packet ordering or undefined behavior, resulting in a denial of service.

