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TI-2020-09921 Aliases CVE-2020-12403GHSA-9h25-47mw-52hh

Out-of-bounds read in nss

Priority MEDIUM 42CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · None · High
Fix status
Partial Red Hat: 21 fixed, 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

A flaw was found in the way CHACHA20-POLY1305 was implemented in NSS in versions before 3.55. When using multi-part Chacha20, it could cause out-of-bounds reads. This issue was fixed by explicitly disabling multi-part ChaCha20 (which was not functioning correctly) and strictly enforcing tag length. The highest threat from this vulnerability is to confidentiality and system availability.

Why it matters now

EPSS 0.01541 75th percentileScored 2026-11-07
Fix Partial Red Hat: 6 advisoriesRed Hat: 21 fixed, 2 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—nssnss 3.55—No fix listedCNA
  • nss Vendor— Affected nss 3.55 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:nss:*:*:*:*:*:*:*:*before 3.55VulnerableMozilla
  • cpe:2.3:a:mozilla:nss:*:*:*:*:*:*:*:* Versions before 3.55 Vulnerable ·Mozilla

Remediation

Red Hat 6 advisories

  • RHSA-2021:1026 Released 2021-03-30 · Red Hat rating Moderate
    nss-softokn security update
    • Red Hat Enterprise Linux ComputeNode EUS (v. 7.7) nss-softokn-3.44.0-9.el7_7, nss-softokn-freebl-3.44.0-9.el7_7
    • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7) nss-softokn-devel-3.44.0-9.el7_7, nss-softokn-freebl-devel-3.44.0-9.el7_7
    • Red Hat Enterprise Linux Server EUS (v. 7.7) nss-softokn-3.44.0-9.el7_7, nss-softokn-3.44.0-9.el7_7.ppc, nss-softokn-devel-3.44.0-9.el7_7 +5
  • RHSA-2021:0949 Released 2021-03-22 · Red Hat rating Low
    Red Hat OpenShift Do openshift/odo-init-image 1.1.3 security update
    • OpenShift Do 1 openshiftdo/odo-init-image-rhel7
  • RHSA-2021:0876 Released 2021-03-16 · Red Hat rating Moderate
    nss and nss-softokn security update
    • Red Hat Enterprise Linux ComputeNode EUS (v. 7.6) nss-3.36.0-9.el7_6, nss-softokn-3.36.0-7.el7_6, nss-softokn-freebl-3.36.0-7.el7_6 +2
    • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6) nss-devel-3.36.0-9.el7_6, nss-pkcs11-devel-3.36.0-9.el7_6, nss-softokn-devel-3.36.0-7.el7_6 +1
    • Red Hat Enterprise Linux Server EUS (v. 7.6) nss-3.36.0-9.el7_6, nss-3.36.0-9.el7_6.ppc, nss-devel-3.36.0-9.el7_6 +11
    • Red Hat Enterprise Linux Server Optional EUS (v. 7.6) nss-pkcs11-devel-3.36.0-9.el7_6, nss-pkcs11-devel-3.36.0-9.el7_6.ppc
    • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) nss-3.36.0-9.el7_6, nss-devel-3.36.0-9.el7_6, nss-softokn-3.36.0-7.el7_6 +5
    • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) nss-pkcs11-devel-3.36.0-9.el7_6
Show 3 more Red Hat advisories
  • RHSA-2021:0758 Released 2021-03-09 · Red Hat rating Moderate
    nss-softokn security update
    • Red Hat Enterprise Linux Server AUS (v. 7.4) nss-softokn-3.28.3-10.el7_4, nss-softokn-devel-3.28.3-10.el7_4, nss-softokn-freebl-3.28.3-10.el7_4 +1
    • Red Hat Enterprise Linux Server E4S (v. 7.4) nss-softokn-3.28.3-10.el7_4, nss-softokn-devel-3.28.3-10.el7_4, nss-softokn-freebl-3.28.3-10.el7_4 +1
    • Red Hat Enterprise Linux Server TUS (v. 7.4) nss-softokn-3.28.3-10.el7_4, nss-softokn-devel-3.28.3-10.el7_4, nss-softokn-freebl-3.28.3-10.el7_4 +1
  • RHSA-2021:0538 Released 2021-02-16 · Red Hat rating Moderate
    nss security and bug fix update
    • Red Hat Enterprise Linux AppStream (v. 8) nss-3.53.1-17.el8_3, nss-devel-3.53.1-17.el8_3, nss-softokn-3.53.1-17.el8_3 +7
  • RHSA-2020:4076 Released 2020-09-29 · Red Hat rating Moderate
    nss and nspr security, bug fix, and enhancement update
    • Red Hat Enterprise Linux Client (v. 7) nspr-4.25.0-2.el7_9, nss-3.53.1-3.el7_9, nss-softokn-3.53.1-6.el7_9 +4
    • Red Hat Enterprise Linux Client Optional (v. 7) nspr-devel-4.25.0-2.el7_9, nss-devel-3.53.1-3.el7_9, nss-pkcs11-devel-3.53.1-3.el7_9 +3
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) nspr-devel-4.25.0-2.el7_9, nss-devel-3.53.1-3.el7_9, nss-pkcs11-devel-3.53.1-3.el7_9 +3
    • Red Hat Enterprise Linux Server (v. 7) nspr-4.25.0-2.el7_9, nspr-4.25.0-2.el7_9.ppc, nspr-devel-4.25.0-2.el7_9 +19
    • Red Hat Enterprise Linux Server Optional (v. 7) nss-pkcs11-devel-3.53.1-3.el7_9, nss-pkcs11-devel-3.53.1-3.el7_9.ppc
    • Red Hat Enterprise Linux Workstation (v. 7) nspr-4.25.0-2.el7_9, nspr-devel-4.25.0-2.el7_9, nss-3.53.1-3.el7_9 +9
    • Red Hat Enterprise Linux Workstation Optional (v. 7) nss-pkcs11-devel-3.53.1-3.el7_9

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
OpenShift Do 1Fixed RHSA-2021:0949
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2021:0538
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2020:4076
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2020:4076
Red Hat Enterprise Linux ComputeNode EUS (v. 7.6)Fixed RHSA-2021:0876
Red Hat Enterprise Linux ComputeNode EUS (v. 7.7)Fixed RHSA-2021:1026
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2020:4076
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6)Fixed RHSA-2021:0876
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7)Fixed RHSA-2021:1026
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2020:4076
Red Hat Enterprise Linux Server AUS (v. 7.4)Fixed RHSA-2021:0758
Red Hat Enterprise Linux Server E4S (v. 7.4)Fixed RHSA-2021:0758
Red Hat Enterprise Linux Server EUS (v. 7.6)Fixed RHSA-2021:0876
Red Hat Enterprise Linux Server EUS (v. 7.7)Fixed RHSA-2021:1026
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2020:4076
Red Hat Enterprise Linux Server Optional EUS (v. 7.6)Fixed RHSA-2021:0876
Red Hat Enterprise Linux Server TUS (v. 7.4)Fixed RHSA-2021:0758
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2020:4076
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2020:4076
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7)Fixed RHSA-2021:0876
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7)Fixed RHSA-2021:0876

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-12403
  2. 2026-10-03 Alias added: GHSA-9h25-47mw-52hh

References

Patch 1

Advisory 1

Other 2

  • TI-2009-03392 The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft… CVSS 3.1CRITICAL 9.8
  • TI-2021-19417 Out-of-bounds write in Mozilla NSS CVSS 3.1CRITICAL 9.8
  • TI-2016-04582 NULL pointer dereference in Mozilla Network Security Services CVSS 3.1HIGH 7.5
  • TI-2016-01772 The s_mp_div function in lib/freebl/mpi/mpi.c in Mozilla Network Security Services (NSS)… CVSS 3.0MEDIUM 6.5
  • TI-2023-04081 Observable discrepancy in Mozilla NSS CVSS 3.1MEDIUM 6.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences