BlackTreeCVE Intelligence
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Full vulnerability report · 2020
CVE-2020-12400High confidence

When converting coordinates from projective to affine, the modular inversion was not performed in constant time, resulting in a possible timing-based side channel attack

Mozilla · Firefox

4.7MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Low, lowered one band.downgradedsince 4 Aug 2024

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 0.27% for the current model date.

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

  1. Confirm that the asset runs Mozilla Firefox and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: No default targetRemediation target: Normal maintenance

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Distribution package intelligence

Release-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.

14 package states
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 releaseSource packageVendor stateFixed versionEvidence
Alpine v3.23v3.23 · communityfirefoxVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.80.0-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.23v3.23 · communitylibrewolfVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.80.0-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.23v3.23 · mainnssVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.3.55-r0Alpine Security Database ↗Source updated 3 Oct 2026
Alpine v3.22v3.22 · communityfirefoxVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.80.0-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.22v3.22 · communitylibrewolfVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.80.0-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.22v3.22 · mainnssVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.3.55-r0Alpine Security Database ↗Source updated 3 Oct 2026
Alpine v3.21v3.21 · communityfirefoxVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.80.0-r0Alpine Security Database ↗Source updated 19 Aug 2026
Alpine v3.21v3.21 · communitylibrewolfVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.80.0-r0Alpine Security Database ↗Source updated 19 Aug 2026
Alpine v3.21v3.21 · mainnssVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.3.55-r0Alpine Security Database ↗Source updated 3 Oct 2026
Debian trixietrixie · sourcenssVendor fix publishedDebian records a fixed source-package version for this release.2:3.55-1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian bookwormbookworm · sourcenssVendor fix publishedDebian records a fixed source-package version for this release.2:3.55-1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian forkyforky · sourcenssVendor fix publishedDebian records a fixed source-package version for this release.2:3.55-1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian sidsid · sourcefirefoxVendor fix publishedDebian records a fixed source-package version for this release.80.0-1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian sidsid · sourcenssVendor fix publishedDebian records a fixed source-package version for this release.2:3.55-1Debian Security Tracker ↗Source updated 6 Oct 2026
Direct vendor intelligence

Authoritative 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.

2 current
CVE-2020-12400 · CSAF 2.0 · revision 32 · interimSUSE Product Security TeamCVE-2020-12400
247 known not affected

The vendor explicitly states that these products are not affected by this CVE.

  • libfreebl3 as component of SUSE CaaS Platform 3.0
  • libsoftokn3 as component of SUSE CaaS Platform 3.0
  • mozilla-nss as component of SUSE CaaS Platform 3.0
  • mozilla-nss-certs as component of SUSE CaaS Platform 3.0
  • mozilla-nss as component of SUSE Container as a Service Platform 2.0
  • libfreebl3 as component of SUSE Enterprise Storage 6
  • libfreebl3-32bit as component of SUSE Enterprise Storage 6
  • libfreebl3-hmac as component of SUSE Enterprise Storage 6
  • libfreebl3-hmac-32bit as component of SUSE Enterprise Storage 6
  • libsoftokn3 as component of SUSE Enterprise Storage 6
  • libsoftokn3-32bit as component of SUSE Enterprise Storage 6
  • libsoftokn3-hmac as component of SUSE Enterprise Storage 6
Summary
When converting coordinates from projective to affine, the modular inversion was not performed in constant time, resulting in a possible timing-based side channel attack. This vulnerability affects Firefox < 80 and Firefox for Android < 80.
Remediation
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
CVE-2020-12400 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitynss: P-384 and P-521 implementation uses a side-channel vulnerable modular inversion function
7 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • nss.src as a component of Red Hat Enterprise Linux 5
  • nss as a component of Red Hat Enterprise Linux 6
  • nss-devel as a component of Red Hat Enterprise Linux 6
  • nss-pkcs11-devel as a component of Red Hat Enterprise Linux 6
  • nss-sysinit as a component of Red Hat Enterprise Linux 6
  • nss-tools as a component of Red Hat Enterprise Linux 6
  • nss.src as a component of Red Hat Enterprise Linux 6
Summary
A side-channel flaw was found in NSS, in the way P-384 and P-521 curves are used in the generation of EDSA signatures, leaking partial information about the ECDSA nonce. Given a small number of ECDSA signatures, this information can be used to steal the private key. The highest threat from this vulnerability is to data confidentiality.
Remediation
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, applications using NSS or NSPR (for example, Firefox) must be restarted for this update to take effect.
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2020-4712

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

When converting coordinates from projective to affine, the modular inversion was not performed in constant time, resulting in a possible timing-based side channel attack. This vulnerability affects Firefox < 80 and Firefox for Android < 80.

What

When converting coordinates from projective to affine, the modular inversion was not performed in constant time, resulting in a possible timing-based side channel attack. This vulnerability affects Firefox < 80 and Firefox for Android < 80.

Why

The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.

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

When converting coordinates from projective to affine, the modular inversion was not performed in constant time, resulting in a possible timing-based side channel attack. This vulnerability affects Firefox < 80 and Firefox for Android < 80.

Why

The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.

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
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

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
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

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 → Observable Discrepancy → 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: a standard category for the underlying weakness.
CWE-203 ↗

CWE-203: Observable Discrepancy. The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.

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:N

Common 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.
CWE-203
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2024-1591Juniper JUNOS: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service zu verursachen, Informationen offenzulegen, Privilegien zu erweitern und Sicherheitsmechanismen inklusive zu umgehen.

Official advisory ↗
BSI · German · WID-SEC-2022-1831Mozilla NSS: Schwachstelle ermöglicht nicht spezifizierten Angriff

Ein Angreifer kann eine Schwachstelle in Mozilla NSS ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20201014Security Bulletin 14 Oct 2020

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 14 Oct 2020, published on 14 October 2020. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-1103Multiples vulnérabilités dans les produits IBM

ERecord?id=CVE-2019-17006 Référence CVE CVE-2019-17007 https://www.cve.org/CVERecord?id=CVE-2019-17007 Référence CVE CVE-2019-17023 https://www.cve.org/CVERecord?id=CVE-2019-17023 Référence CVE CVE-2019-17546 https://www.cve.org/CVERecord?id=CVE-2019-17546 Référence CVE CVE-2019-6128 https://www.cve.org/CVERecord?id=CVE-2019-6128 Référence CVE CVE-2019-7317 https://www.cve.org/CVERecord?id=CVE-2019-7317 Référence CVE CVE-2019-8331 https://www.cve.org/CVERecord?id=CVE-2019-8331 Référence CVE CVE-2020-11022 https://www.cve.org/CVERecord?id=CVE-2020-11022 Référence CVE CVE-2020-11023 https://www.cve.org/CVERecord?id=CVE-2020-11023 Référence CVE CVE-2020-12400 https://www.cve.org/CVERecord?id=CVE-2020-12400 Référence CVE CVE-2020-12401 https://www.cve.org/CVERecord?id=CVE-2020-12401 Référence CVE CVE-2020-12403 https://www.cve.org/CVERecord?id=CVE-2020-12403 Référence CVE CVE-2020-15110 https://www.cve.org/CVERecord?id=CVE-2020-15110 Référence CVE CVE-2020-18768 https://www.cve.org/CVERecord?id=CVE-2020-18768 Référence CVE CVE-2020-19131 https://www.cve.org/CVERecord?id=CVE-2020-19131 Référence CVE CVE-2020-19144 https://www.cve.org/CVERecord?id=CVE-2020-19144 Référence CVE CVE-2020-19189 https://www.cve.org/CVERecord?id=CVE-2020-19189 Référence CVE CVE-2020-23064 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0575Multiples vulnérabilités dans les produits Juniper Networks

ord?id=CVE-2019-17006 Référence CVE CVE-2019-17023 https://www.cve.org/CVERecord?id=CVE-2019-17023 Référence CVE CVE-2019-17567 https://www.cve.org/CVERecord?id=CVE-2019-17567 Référence CVE CVE-2019-20149 https://www.cve.org/CVERecord?id=CVE-2019-20149 Référence CVE CVE-2019-9517 https://www.cve.org/CVERecord?id=CVE-2019-9517 Référence CVE CVE-2020-11668 https://www.cve.org/CVERecord?id=CVE-2020-11668 Référence CVE CVE-2020-11984 https://www.cve.org/CVERecord?id=CVE-2020-11984 Référence CVE CVE-2020-11993 https://www.cve.org/CVERecord?id=CVE-2020-11993 Référence CVE CVE-2020-12362 https://www.cve.org/CVERecord?id=CVE-2020-12362 Référence CVE CVE-2020-12400 https://www.cve.org/CVERecord?id=CVE-2020-12400 Référence CVE CVE-2020-12401 https://www.cve.org/CVERecord?id=CVE-2020-12401 Référence CVE CVE-2020-12402 https://www.cve.org/CVERecord?id=CVE-2020-12402 Référence CVE CVE-2020-12403 https://www.cve.org/CVERecord?id=CVE-2020-12403 Référence CVE CVE-2020-13938 https://www.cve.org/CVERecord?id=CVE-2020-13938 Référence CVE CVE-2020-13950 https://www.cve.org/CVERecord?id=CVE-2020-13950 Référence CVE CVE-2020-14145 https://www.cve.org/CVERecord?id=CVE-2020-14145 Référence CVE CVE-2020-1927 https://www.cve.org/CVERecord?id=CVE-2020-1927 Référence CVE CVE-2020-1934 https://www.cve.org/CVERecord?id=CVE

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-267Multiples vulnérabilités dans Juniper Networks Junos Space

d?id=CVE-2020-10754 Référence CVE CVE-2020-10757 https://www.cve.org/CVERecord?id=CVE-2020-10757 Référence CVE CVE-2020-10769 https://www.cve.org/CVERecord?id=CVE-2020-10769 Référence CVE CVE-2020-10772 https://www.cve.org/CVERecord?id=CVE-2020-10772 Référence CVE CVE-2020-10942 https://www.cve.org/CVERecord?id=CVE-2020-10942 Référence CVE CVE-2020-11565 https://www.cve.org/CVERecord?id=CVE-2020-11565 Référence CVE CVE-2020-11868 https://www.cve.org/CVERecord?id=CVE-2020-11868 Référence CVE CVE-2020-12049 https://www.cve.org/CVERecord?id=CVE-2020-12049 Référence CVE CVE-2020-12243 https://www.cve.org/CVERecord?id=CVE-2020-12243 Référence CVE CVE-2020-12400 https://www.cve.org/CVERecord?id=CVE-2020-12400 Référence CVE CVE-2020-12401 https://www.cve.org/CVERecord?id=CVE-2020-12401 Référence CVE CVE-2020-12402 https://www.cve.org/CVERecord?id=CVE-2020-12402 Référence CVE CVE-2020-12403 https://www.cve.org/CVERecord?id=CVE-2020-12403 Référence CVE CVE-2020-12653 https://www.cve.org/CVERecord?id=CVE-2020-12653 Référence CVE CVE-2020-12654 https://www.cve.org/CVERecord?id=CVE-2020-12654 Référence CVE CVE-2020-12662 https://www.cve.org/CVERecord?id=CVE-2020-12662 Référence CVE CVE-2020-12663 https://www.cve.org/CVERecord?id=CVE-2020-12663 Référence CVE CVE-2020-12770 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2020-AVI-543Multiples vulnérabilités dans Mozilla Firefox

De multiples vulnérabilités ont été découvertes dans Mozilla Firefox. Elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un contournement de la politique de sécurité et une atteinte à la confidentialité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2020-AVI-532Multiples vulnérabilités dans Mozilla Firefox

De multiples vulnérabilités ont été découvertes dans Mozilla Firefox. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un contournement de la politique de sécurité et une atteinte à l'intégrité des données.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2020-012325Firefox における情報漏えいに関する脆弱性

Firefox には、情報漏えいに関する脆弱性が存在します。

Official advisory ↗
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
Affected
Fixed
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, applications using NSS or NSPR (for example, Firefox) must be restarted for this update to take effect.
Action
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 8 Oct 2020 · Last source change 4 Aug 2024, 11:56 UTC · CWE-203 · Observable Discrepancy

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2020-4712
Product sourceCNA
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    unspecified < 80 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    unspecified < 80 · Fixed: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, applications using NSS or NSPR (for example, Firefox) must be restarted for this update to take effect.
    Red Hat Product Security ↗
  2. Remediation statusRemediation status changed from Awaiting fix to Patch available.
    Before
    Awaiting fix
    After
    Patch available
    Red Hat Product Security ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release recorded from official guidance
ENISA EUVD · EUVD-2020-4712↗Vendor CSAF · SUSE Product Security Team↗Red Hat Product Security security advisory↗CVE authority or vendor reference↗Vendor advisory↗Vendor advisory↗Official CVE record (CNA and ADP data)↗NVD record↗
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.
Free version - for non-commercial use only.CVE-2020-12400 · cve.blacktree.nl