Evidence used
- No CISA KEV confirmation is currently recorded.
- The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
- EPSS is 14.30% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2019
CVE-2019-1551High confidence
rsaz_512_sqr overflow bug on x86_64
OpenSSL · OpenSSL
5.3MediumCVSS 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:High, raised one band.upgradedsince 6 Oct 2026
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict the affected network interface to trusted sources where business-safe.
- 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-r3 | Alpine Security Database ↗Source updated 3 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-r3 | Alpine Security Database ↗Source updated 3 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-r3 | Alpine Security Database ↗Source updated 3 Oct 2026 |
| Debian trixietrixie · source | openssl | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.1.1e-1 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian bookwormbookworm · source | openssl | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.1.1e-1 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian forkyforky · source | openssl | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.1.1e-1 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian sidsid · source | openssl | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.1.1e-1 | Debian Security Tracker ↗Source updated 6 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-2019-1551 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityopenssl: Integer overflow in RSAZ modular exponentiation on x86_64No 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 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
- compat-openssl10.src as a component of Red Hat Enterprise Linux 8
- openssl.src as a component of Red Hat JBoss Enterprise Application Platform 6
- openssl.src as a component of Red Hat JBoss Enterprise Web Server 2
- Summary
- An integer overflow was found in the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. As per upstream: * No EC algorithms are affected. * Attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are not believed likely. * Attacks against DH512 are considered just feasible. However, for an attack the target would have to re-use the DH512 private key, which is not recommended anyway. * Also applications directly using the low level API BN_mod_exp may be affected if they use BN_FLG_CONSTTIME
- 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
There is an overflow bug in the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH512 are considered just feasible. However, for an attack the target would have to re-use the DH512 private key, which is not recommended anyway. Also applications directly using the low level API BN_mod_exp may be affected if they use BN_FLG_CONSTTIME. Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d). Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t).
What
There is an overflow bug in the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH512 are considered just feasible. However, for an attack the target would have to re-use the DH512 private key, which is not recommended anyway. Also applications directly using the low level API BN_mod_exp may be affected if they use BN_FLG_CONSTTIME. Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d). Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t).
Why
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
There is an overflow bug in the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH512 are considered just feasible. However, for an attack the target would have to re-use the DH512 private key, which is not recommended anyway. Also applications directly using the low level API BN_mod_exp may be affected if they use BN_FLG_CONSTTIME. Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d). Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t).
Why
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. 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
- a network path → Integer Overflow or Wraparound → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-190 ↗
CWE-190: Integer Overflow or Wraparound. The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CLowConfidentiality impact: A successful attack can cause a limited 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
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
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. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 6 Dec 2019 · Last source change 16 Sept 2024, 19:40 UTC · CWE-190 · Integer Overflow or Wraparound
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-2019-10108
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- Vendor guidanceAuthoritative vendor guidance changed from remediation: access.redhat.com/CVE-2019-1551 to advisory no longer present in the provider's current catalogue.Red Hat Product Security ↗
- Before
- remediation: access.redhat.com/CVE-2019-1551
- 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 1.1.1e (Affected 1.1.1-1.1.1d); Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t) · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
- After
- Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d); Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t) · 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
- ENISA EUVD mappingEUVD-2019-10108 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2019-10108"}
- Vendor guidanceAuthoritative vendor guidance changed: added patch: oracle.com/cpuApr2021.html; added patch: oracle.com/cpujan2021.html; removed vendor advisory: debian.org/dsa-4594; removed vendor advisory: debian.org/dsa-4855; 3 further additions; 7 further removals.oracle.com ↗
- Before
- vendor advisory: debian.org/dsa-4594 · vendor advisory: debian.org/dsa-4855 · vendor advisory: lists.fedoraproject.org/DDHOAATPWJCXRNFMJ2SASDBBNU5RJONY · 6 more references
- After
- patch: oracle.com/cpuApr2021.html · patch: oracle.com/cpujan2021.html · patch: oracle.com/cpujul2020.html · 2 more references
- Affected versionsThe structured affected or fixed version information changed.CNA ↗
- Before
- Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d); Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t) · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- After
- Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d); Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t) · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
- Remediation statusRemediation status changed from Awaiting fix to Patch available.oracle.com ↗
- Before
- Awaiting fix
- After
- Patch available
- SeveritySeverity changed from Unknown to Medium.NIST NVD ↗
- Before
- Unknown
- After
- Medium
- CVSS scoreCVSS score changed from not recorded to 5.3 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N).NIST NVD ↗
- Before
- not recorded
- After
- 5.3 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
CVE published
Fixed release or patch reference recorded
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.