Evidence used
- No CISA KEV confirmation is currently recorded.
- Exploitation requires an existing local or physical foothold with privileges.
- EPSS is 1.17% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2019
CVE-2019-1547High confidence
ECDSA remote timing attack
OpenSSL · OpenSSL
4.7MediumCVSS 3.1
Scheduled
Patch availableMedium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Low, lowered one band.downgradedsince 16 Sep 2024
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs OpenSSL OpenSSL and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Distribution package intelligence
7 package statesRelease-specific package status
Alpine, Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.
Repository candidate not checked
A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.
| Distribution release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Alpine v3.23v3.23 · main | openssl | Vendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected. | 1.1.1d-r1 | Alpine Security Database ↗Source updated 23 Oct 2026 |
| Alpine v3.22v3.22 · main | openssl | Vendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected. | 1.1.1d-r1 | Alpine Security Database ↗Source updated 23 Oct 2026 |
| Alpine v3.21v3.21 · main | openssl | Vendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected. | 1.1.1d-r1 | Alpine Security Database ↗Source updated 23 Oct 2026 |
| Debian trixietrixie · source | openssl | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.1.1d-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian bookwormbookworm · source | openssl | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.1.1d-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian forkyforky · source | openssl | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.1.1d-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian sidsid · source | openssl | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.1.1d-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
Direct vendor intelligence
0 current · 1 archivedAuthoritative vendor CSAF and VEX advisories
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
CVE-2019-1547 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityopenssl: side-channel weak encryption vulnerabilityNo longer in the provider’s current catalogue
The vendor explicitly identifies these products as affected by this CVE.
- openssl as a component of Red Hat Enterprise Linux 6
- openssl-devel as a component of Red Hat Enterprise Linux 6
- openssl-perl as a component of Red Hat Enterprise Linux 6
- openssl-static as a component of Red Hat Enterprise Linux 6
- openssl.src as a component of Red Hat Enterprise Linux 6
- openssl as a component of Red Hat Enterprise Linux 7
- openssl-devel as a component of Red Hat Enterprise Linux 7
- openssl-libs as a component of Red Hat Enterprise Linux 7
- openssl-perl as a component of Red Hat Enterprise Linux 7
- openssl-static as a component of Red Hat Enterprise Linux 7
- openssl.src as a component of Red Hat Enterprise Linux 7
- compat-openssl10 as a component of Red Hat Enterprise Linux 8
- Summary
- Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s).
- Remediation
- Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Patch available01
What, why and how
Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s).
What
Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s).
Why
The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.
How
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s).
Why
The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.
How
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- local access → vulnerable operation → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Local
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- None
- Attack complexity
- High: exploitation depends on specific conditions
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration. - CWE not yet assigned
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.INoneIntegrity impact: No direct loss is represented by this metric.ANoneAvailability impact: No direct loss is represented by this metric.- Post-exploitation / living off the land
- The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Action
- Apply the fixed release for the affected product branch as recorded by Red Hat Product Security. Validate the exact product and build in the linked advisory before deployment.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 10 Sept 2019 · Last source change 16 Sept 2024, 16:33 UTC · CWE not yet assigned
CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source FIRST · tracked since 2026-09-01
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2019-10104
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceUnavailable
NVD statusNVD modified after enrichment
Missing structured fields: CWE classification. Missing data is not evidence of low risk; review the primary advisory.
Material change intelligence
View recent updates ↗What changed after publication
- Vendor guidanceAuthoritative vendor guidance changed from remediation: access.redhat.com/CVE-2019-1547 to advisory no longer present in the provider's current catalogue.Red Hat Product Security ↗
- Before
- remediation: access.redhat.com/CVE-2019-1547
- After
- advisory no longer present in the provider's current catalogue
- Affected versionsThe structured affected or fixed version information changed.Red Hat Product Security ↗
- Before
- Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c); Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k); Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s) · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- After
- Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c); Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k); Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s) · Fixed: Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
- Remediation statusRemediation status changed from Awaiting fix to Patch available.Red Hat Product Security ↗
- Before
- Awaiting fix
- After
- Patch available
- ENISA EUVD mappingEUVD-2019-10104 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2019-10104"}
- Vendor guidanceAuthoritative vendor guidance changed: added vendor advisory: openssl.org/20190910.txt; removed vendor advisory: debian.org/dsa-4539; removed vendor advisory: debian.org/dsa-4540; 10 further removals.openssl.org ↗
- Before
- vendor advisory: debian.org/dsa-4539 · vendor advisory: debian.org/dsa-4540 · vendor advisory: lists.fedoraproject.org/GY6SNRJP2S7Y42GIIDO3HXPNMDYN2U3A · 9 more references
- After
- vendor advisory: openssl.org/20190910.txt
- SeveritySeverity changed from Unknown to Medium.NIST NVD ↗
- Before
- Unknown
- After
- Medium
- CVSS scoreCVSS score changed from not recorded to 4.7 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N).NIST NVD ↗
- Before
- not recorded
- After
- 4.7 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N)
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
CVE published
Fixed release recorded from official guidance
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.