CVE-2018-0734 — Timing attack against DSA
The OpenSSL DSA signature algorithm has been shown to be vulnerable to a timing side channel attack. An attacker could use variations in the signing algorithm to recover the private key. Fixed in OpenSSL 1.1.1a (Affected 1.1.1). Fixed in OpenSSL 1.1.0j (Affected 1.1.0-1.1.0i). Fixed in OpenSSL 1.0.2q (Affected 1.0.2-1.0.2p).
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 12.2% (30-day exploitation probability)+14
- Technical severity (medium)+3
- Automatable exploitation (SSVC)+3
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 — www.oracle.com (NIST National Vulnerability Database)
- Documented patch — www.oracle.com (NIST National Vulnerability Database)
- Documented patch — www.oracle.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 (Canonical Ubuntu Linux, Debian Debian Linux, Netapp Cloud Backup…).
- 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.
- EPSS ahead of 96% of scored CVEs: prioritize it in the patch queue.
- Search available logs for exploit probes matching the vulnerability class (cryptography), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Canonical | Ubuntu Linux | version 14.04version 16.04version 18.04version 18.10 | Vulnerable | NIST National Vulnerability Database |
| Debian | Debian Linux | version 9.0 | Vulnerable | NIST National Vulnerability Database |
| Netapp | Cloud Backup | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Cn1610 Firmware | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Oncommand Unified Manager | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Santricity Smi-s Provider | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Snapcenter | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Steelstore | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Netapp | Storage Automation Store | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Nodejs | Node.js | ≥ 8.0.0 and ≤ 8.8.1≥ 6.0.0 and ≤ 6.8.1version 10.13.0≥ 10.0.0 and ≤ 10.12.0≥ 6.9.0 and < 6.15.0≥ 11.0.0 and < 11.3.0≥ 8.9.0 and < 8.14.0 | Vulnerable | NIST National Vulnerability Database |
| Openssl | Openssl | ≥ 1.0.2 and ≤ 1.0.2p≥ 1.1.0 and ≤ 1.1.0iversion 1.1.1 | Vulnerable | NIST National Vulnerability Database |
| Openssl | Openssl | version Fixed in OpenSSL 1.1.1a (Affected 1.1.1)version Fixed in OpenSSL 1.1.0j (Affected 1.1.0-1.1.0i)version Fixed in OpenSSL 1.0.2q (Affected 1.0.2-1.0.2p) | Vulnerable | CVE Program (cve.org) e CISA ADP |
| Oracle | Api Gateway | version 11.1.2.4.0 | Vulnerable | NIST National Vulnerability Database |
| Oracle | E-business Suite Technology Stack | version 1.0.0version 0.9.8version 1.0.1 | Vulnerable | NIST National Vulnerability Database |
| Oracle | Enterprise Manager Base Platform | version 13.3.0.0.0version 13.2.0.0.0version 12.1.0.5.0 | Vulnerable | NIST National Vulnerability Database |
| Oracle | Enterprise Manager Ops Center | version 12.3.3 | Vulnerable | NIST National Vulnerability Database |
| Oracle | Mysql Enterprise Backup | ≥ 3.0 and ≤ 3.12.3≥ 4.0 and ≤ 4.1.2 | Vulnerable | NIST National Vulnerability Database |
| Oracle | Peoplesoft Enterprise Peopletools | version 8.56version 8.55version 8.57 | Vulnerable | NIST National Vulnerability Database |
| Oracle | Primavera P6 Professional Project Management | ≥ 17.7 and ≤ 17.12version 8.4version 15.1version 15.2version 16.1version 16.2version 18.8 | Vulnerable | NIST National Vulnerability Database |
| Oracle | Tuxedo | version 12.1.1.0.0 | 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 |
|---|---|---|---|---|---|
| 5.9 | CVSS 3.1 | Medium | 2.2 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
| 4.3 | CVSS 2.0 | Medium | 8.6 | 2.9 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 12.15%
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).
- Check TLS negotiations and unexpected certificates in the component’s traffic.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · openssl/openssl
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 5.9
- Source status changed · → Modified
- Record created in this database
- 2018
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
29 on the record
- www.openssl.org/news/secadv/20181030.txt
- www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html
- www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html
- www.oracle.com/technetwork/security-advisory/cpujul2019-5072835.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y3IV
- security.netapp.com/advisory/ntap-20181105-0002/
- git.openssl.org/gitweb/
- access.redhat.com/errata/RHSA-2019:3700
- access.redhat.com/errata/RHSA-2019:2304
- access.redhat.com/errata/RHSA-2019:3932
- www.debian.org/security/2018/dsa-4348
- www.securityfocus.com/bid/105758
- www.oracle.com/security-alerts/cpuapr2020.html
- security.netapp.com/advisory/ntap-20190423-0002/
- www.oracle.com/security-alerts/cpujan2020.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EWC4
- access.redhat.com/errata/RHSA-2019:3935
- lists.opensuse.org/opensuse-security-announce/2019-06/msg00030.html
- usn.ubuntu.com/3840-1/
- www.debian.org/security/2018/dsa-4355
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZBEV
- git.openssl.org/gitweb/
- www.tenable.com/security/tns-2018-16
- security.netapp.com/advisory/ntap-20190118-0002/
- www.tenable.com/security/tns-2018-17
- nodejs.org/en/blog/vulnerability/november-2018-security-releases/
- git.openssl.org/gitweb/
- lists.opensuse.org/opensuse-security-announce/2019-07/msg00056.html
- access.redhat.com/errata/RHSA-2019:3933
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-84783 Use-After-Free in X.509 Extension Cache Under Concurrent Use 16d
- High CVE-2026-84784 QUIC: Unbounded RETIRE_CONNECTION_ID Backlog 16d
- High CVE-2026-84782 DTLS Retransmits Handshake Messages From a Stale Buffer Offset 16d
- Medium CVE-2026-75806 Unauthenticated and Undersized DTLS 1.2 AEAD Record Causes DoS 16d
- Medium CVE-2026-75805 NULL Pointer Dereference in CMP Client Revocation Response Handling 16d
- Low CVE-2026-77696 Timing Side-Channel in SM2 Signature Generation 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-2018-0734 is "Timing attack against DSA", rated Medium. It affects Ubuntu Linux (Canonical); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.9 describes technical severity. EPSS 12.15% 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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