CVE-2023-0361 — A timing side-channel in the handling of RSA ClientKeyExchange messages was discovered in GnuTLS....
A timing side-channel in the handling of RSA ClientKeyExchange messages was discovered in GnuTLS. This side-channel can be sufficient to recover the key encrypted in the RSA ciphertext across a network in a Bleichenbacher style attack. To achieve a successful decryption the attacker would need to send a large amount of specially crafted messages to the vulnerable server. By recovering the secret from the ClientKeyExchange message, the attacker would be able to decrypt the application data exchanged over that connection.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 1.4% (30-day exploitation probability)+11
- Technical severity (high)+6
- CISA SSVC: exploitation "poc"+5
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Debian Debian Linux, Fedoraproject Fedora, Gnu Gnutls…).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (info disclosure), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Debian | Debian Linux | version 10.0 | Vulnerable | NIST National Vulnerability Database |
| Fedoraproject | Fedora | version 36version 37version 38 | Vulnerable | NIST National Vulnerability Database |
| Gnu | Gnutls | version 3.6.8-11.el8_2 | Vulnerable | NIST National Vulnerability Database |
| Netapp | Active Iq Unified Manager | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Converged Systems Advisor Agent | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Ontap Select Deploy Administration Utility | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Red Hat | Enterprise Linux | version 8.0version 9.0 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.5 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 7.4 | CVSS 3.1 | High | 2.2 | 5.2 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.4 | CVSS 3.1 | High | 2.2 | 5.2 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database |
| 7.4 | CVSS 3.1 | High | — | — | CISA-ADP via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Look for anomalous data read/export volumes and access to sensitive records.
Timeline
What happened to this CVE, newest first.
- 2026
- SSVC assessment updated
- Record published
- Fix documented
- Affected products added · gnu/gnutls, redhat/enterprise linux, debian/debian linux, fedoraproject/fedora, netapp/active iq unified manager, netapp
- CVSS changed · 7.4
- Source status changed · → Modified
- Record created in this database
- 2023
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
21 on the record
- gitlab.com/gnutls/gnutls/-/issues/1050
- github.com/tlsfuzzer/tlsfuzzer/pull/679
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS4K
- lists.debian.org/debian-lts-announce/2023/02/msg00015.html
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WS4KVD
- security.netapp.com/advisory/ntap-20230725-0005/
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UFIA3X
- nvd.nist.gov/vuln/detail/CVE-2023-0361
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS4K
- github.com/advisories/GHSA-5547-g9w2-52xj
- security.netapp.com/advisory/ntap-20230725-0005
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/Z634YB
- security.netapp.com/advisory/ntap-20230324-0005
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z634
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UFIA
- access.redhat.com/security/cve/CVE-2023-0361
- security.netapp.com/advisory/ntap-20230324-0005/
- cert-portal.siemens.com/productcert/html/ssa-398330.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z634
- cert-portal.siemens.com/productcert/html/ssa-806742.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UFIA
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-104046 Sssd: sssd: denial of service via incomplete identity provider authentication requests 9d
- Medium CVE-2026-104045 Sssd: sssd: denial of service via race condition in autofs responder 9d
- High CVE-2026-104048 Sssd: sssd: authorization bypass via cross-domain username collision in hbac evaluation 9d
- Medium CVE-2026-104047 Sssd: sssd: information disclosure via query injection in entra id lookups 9d
- High CVE-2026-102558 Libsoup: libsoup: heap buffer overflow during websocket receive-buffer growth 16d
- High CVE-2026-102555 Libsoup: libsoup: heap buffer overflow via uninitialized length in data-uri base64 decoding 16d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2023-0361 is "A timing side-channel in the handling of RSA ClientKeyExchange messages was discovered in GnuTLS....", rated High. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.4 describes technical severity. EPSS 1.42% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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