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NVD / CVE Program· CNA redhat

CVE-2020-1749: A flaw was found in the Linux kernel's implementation of some networking protocols in IPsec, such as VXLAN and GENEVE tunnels over IPv6.

Noroxi assessment

Priority: Monitor (action score 30/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 1.2% (FIRST EPSS); higher than 68.9% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: linux (Debian:12) 5.4.6-1; kernel-debug (openSUSE:Leap 15.1) 4.12.14-lp151.28.63.1; kernel-default (openSUSE:Leap 15.1) 4.12.14-lp151.28.63.1.
  • Mentioned 4 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to linux (Debian:12) 5.4.6-1; kernel-debug (openSUSE:Leap 15.1) 4.12.14-lp151.28.63.1; kernel-default (openSUSE:Leap 15.1) 4.12.14-lp151.28.63.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A flaw was found in the Linux kernel's implementation of some networking protocols in IPsec, such as VXLAN and GENEVE tunnels over IPv6. When an encrypted tunnel is created between two hosts, the kernel isn't correctly routing tunneled data over the encrypted link; rather sending the data unencrypted. This would allow anyone in between the two endpoints to read the traffic unencrypted. The main threat from this vulnerability is to data confidentiality.

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
Sep 9, 2020
Updated
Jun 16, 2026
EPSS
1.2% · 68th percentile

Report tools

JSON

Action score

30

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.2%

CNA vs NVD score

NVD
7.5
CNA · redhat
7.5
agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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  • when exploit code appears or is weaponized
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  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel
redhatenterprise linux
redhatenterprise mrg

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Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernelall versions
  • redhat enterprise linux7.0
  • redhat enterprise mrg2.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Kernel kernel

    • 5.5affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 5.4.6-15.4.6-1
openSUSE:Leap 15.1kernel-debugbefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
openSUSE:Leap 15.1kernel-defaultbefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
openSUSE:Leap 15.1kernel-docsbefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
openSUSE:Leap 15.1kernel-kvmsmallbefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
openSUSE:Leap 15.1kernel-obs-buildbefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
openSUSE:Leap 15.1kernel-obs-qabefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
openSUSE:Leap 15.1kernel-sourcebefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
openSUSE:Leap 15.1kernel-symsbefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
openSUSE:Leap 15.1kernel-vanillabefore 4.12.14-lp151.28.63.14.12.14-lp151.28.63.1
Red Hat:enterprise_linux:7::serverkernelbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-abi-whitelistsbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-altbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-bootwrapperbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-debugbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-debug-debuginfobefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-debug-develbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-debuginfobefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-debuginfo-common-ppc64lebefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-develbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-docbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-toolsbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-tools-debuginfobefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a
Red Hat:enterprise_linux:7::serverkernel-tools-libsbefore 0:4.14.0-115.35.1.el7a0:4.14.0-115.35.1.el7a

+96

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2020-14356Aug 19, 2020 · A flaw null pointer dereference in the Linux kernel cgroupv2 subsystem in versions before 5.7.10 was found in the way when reboot the system
    31Monitor
  • ← EarlierCVE-2020-10720Sep 3, 2020 · A flaw was found in the Linux kernel's implementation of GRO in versions before 5.2.
    22Monitor
  • Later →CVE-2020-25211Sep 9, 2020 · In the Linux kernel through 5.8.7, local attackers able to inject conntrack netlink configuration could overflow a local buffer, causing cra
    24Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:linux5.4.6-1 · Debian:12Package registry (OSV)
opensuse:kernel-debug4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
opensuse:kernel-default4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
opensuse:kernel-docs4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
opensuse:kernel-kvmsmall4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
opensuse:kernel-obs-build4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
opensuse:kernel-obs-qa4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
opensuse:kernel-source4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
opensuse:kernel-syms4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
opensuse:kernel-vanilla4.12.14-lp151.28.63.1 · openSUSE:Leap 15.1Package registry (OSV)
red hat:kernel0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-abi-whitelists0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-alt0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-bootwrapper0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-debug0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-debug-debuginfo0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-debuginfo0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-debuginfo-common-ppc64le0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-devel0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-doc0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-tools0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
red hat:kernel-tools-debuginfo0:4.14.0-115.35.1.el7a · Red Hat:enterprise_linux:7::serverPackage registry (OSV)
suse:kernel-livepatch-SLE15_Update_173-2.1 · SUSE:Linux Enterprise Live Patching 15Package registry (OSV)
suse:kgraft-patch-SLE12-SP4_Update_103-2.1 · SUSE:Linux Enterprise Live Patching 12 SP4Package registry (OSV)
suse:kgraft-patch-SLE12-SP4_Update_113-2.1 · SUSE:Linux Enterprise Live Patching 12 SP4Package registry (OSV)
suse:kgraft-patch-SLE12-SP4_Update_48-2.1 · SUSE:Linux Enterprise Live Patching 12 SP4Package registry (OSV)
suse:kgraft-patch-SLE12-SP4_Update_57-2.1 · SUSE:Linux Enterprise Live Patching 12 SP4Package registry (OSV)
suse:kgraft-patch-SLE12-SP4_Update_66-2.1 · SUSE:Linux Enterprise Live Patching 12 SP4Package registry (OSV)
suse:kgraft-patch-SLE12-SP4_Update_76-2.1 · SUSE:Linux Enterprise Live Patching 12 SP4Package registry (OSV)
suse:kgraft-patch-SLE12-SP4_Update_85-2.1 · SUSE:Linux Enterprise Live Patching 12 SP4Package registry (OSV)

+4

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
none
Availability
none
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
None
Availability impact
None

Weakness class (CWE)

CWE-319 · Cleartext Transmission of Sensitive Information

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records