CVE-2016-5285: A Null pointer dereference vulnerability exists in Mozilla Network Security Services due to a missing NULL che

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HIGH 7.5REMOTEWATCHLISTUPGRADEMITIGATEMITIGATE

CVE-2016-5285 is a high-severity flaw (CVSS 7.5) affecting nss, debian linux, enterprise linux. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A Null pointer dereference vulnerability exists in Mozilla Network Security Services due to a missing NULL check in PK11_SignWithSymKey / ssl3_ComputeRecordMACConstantTime, which could let a remote malicious user cause a Denial of Service.

Why this priority

High severity
Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	2.3% (top 17%)
CISA exploited list	No
Weakness	CWE-476
Published	2019-11-15
Last modified	2026-06-17

Publisher (CNA): Mozilla Corporation · Vendor: avaya · debian · mozilla · redhat · suse

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2019-11-15 16:15 UTCPublished CVE record published
2026-06-17 00:49 UTCUpdated Record last modified

mozilla nss UPGRADE

Affected: < 3.26

Fixed in: 3.26

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy nss || rpm -q nss || nss --version

2. UPGRADE to 3.26 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade nss

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade nss

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

debian debian linux MITIGATE

Affected: 8.0 · 9.0 · 10.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

redhat enterprise linux MITIGATE

Affected: 5.0 · 6.0 · 7.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 5.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

suse linux enterprise server MITIGATE

Affected: 11 sp2

Fixed in: no fixed release known

Safe to downgrade to: a release before 11

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

avaya aura application enablement services UPGRADE

Affected: >= 6.1 and <= 6.3.3 · 7.0

Fixed in: newer than 6.3.3

Safe to downgrade to: a release before 6.1

1. Check installed version

apt-cache policy aura-application-enablement-services || rpm -q aura-application-enablement-services || aura-application-enablement-services --version

2. UPGRADE to newer than 6.3.3 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade aura-application-enablement-services

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade aura-application-enablement-services

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 6.1 (Debian / Ubuntu)

apt-cache madison aura-application-enablement-services sudo apt install aura-application-enablement-services=<VERSION_BEFORE_6.1> sudo apt-mark hold aura-application-enablement-services

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list aura-application-enablement-services sudo dnf downgrade aura-application-enablement-services-<VERSION_BEFORE_6.1> sudo dnf versionlock add aura-application-enablement-services

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

avaya aura application server 5300 DOWNGRADE

Affected: 3.0 · 3.0 sp1 · 3.0 sp10 · 3.0 sp10.1 · 3.0 sp11 · 3.0 sp11.1 · 3.0 sp12 · 3.0 sp12.1

Fixed in: no fixed release known

Safe to downgrade to: a release before 3.0

1. Check installed version

apt-cache policy aura-application-server-5300 || rpm -q aura-application-server-5300 || aura-application-server-5300 --version

2. No fixed release: DOWNGRADE to a release before 3.0 (Debian / Ubuntu)

apt-cache madison aura-application-server-5300 sudo apt install aura-application-server-5300=<VERSION_BEFORE_3.0> sudo apt-mark hold aura-application-server-5300

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list aura-application-server-5300 sudo dnf downgrade aura-application-server-5300-<VERSION_BEFORE_3.0> sudo dnf versionlock add aura-application-server-5300

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2016-5285?

nss: upgrade to 3.26; debian linux: mitigate or apply the listed mitigation; enterprise linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2016-5285 being exploited?

CVE-2016-5285 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2016-5285 affect?

CVE-2016-5285 affects nss, debian linux, enterprise linux. Severity is high (CVSS 7.5). A Null pointer dereference vulnerability exists in Mozilla Network Security Services due to a missing NULL check in PK11_SignWithSymKey / ssl3_ComputeRecordMACConstantTime, which could let a remote malicious user cause a Denial of Service.

How urgent is CVE-2016-5285?

Priority 57/100. High severity; Remotely exploitable, no login, no user action; On your watchlist

Software pages

Debian vulnerabilities

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References

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