Cleartext transmission of sensitive information in Linux kernel
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Partial Red Hat: 16 fixed, 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-319.
Summary
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.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | kernel | 5.5 | — | No fix listed | CNA |
- kernel VendorLinux Affected 5.5 Fixed in — No fix listed CNA
Remediation
Red Hat 5 advisories
- RHSA-2021:0354 Released 2021-02-02 · Red Hat rating Importantkernel-alt security update
- Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) kernel-4.14.0-115.35.1.el7a, kernel-abi-whitelists-4.14.0-115.35.1.el7a, kernel-alt-4.14.0-115.35.1.el7a +8
- Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) kernel-debug-devel-4.14.0-115.35.1.el7a, kernel-tools-libs-devel-4.14.0-115.35.1.el7a
- RHSA-2020:4060 Released 2020-09-29 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux Client (v. 7) bpftool-3.10.0-1160.el7, kernel-3.10.0-1160.el7, kernel-abi-whitelists-3.10.0-1160.el7 +8
- Red Hat Enterprise Linux Client Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.el7
- Red Hat Enterprise Linux ComputeNode (v. 7) bpftool-3.10.0-1160.el7, kernel-3.10.0-1160.el7, kernel-abi-whitelists-3.10.0-1160.el7 +8
- Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.el7
- Red Hat Enterprise Linux Server (v. 7) bpftool-3.10.0-1160.el7, kernel-3.10.0-1160.el7, kernel-abi-whitelists-3.10.0-1160.el7 +11
- Red Hat Enterprise Linux Server Optional (v. 7) kernel-debug-devel-3.10.0-1160.el7, kernel-tools-libs-devel-3.10.0-1160.el7
- Red Hat Enterprise Linux Workstation (v. 7) bpftool-3.10.0-1160.el7, kernel-3.10.0-1160.el7, kernel-abi-whitelists-3.10.0-1160.el7 +8
- Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.el7
- RHSA-2020:4062 Released 2020-09-29 · Red Hat rating Importantkernel-rt security and bug fix update
- Red Hat Enterprise Linux for Real Time (v. 7) kernel-rt-3.10.0-1160.rt56.1131.el7, kernel-rt-debug-3.10.0-1160.rt56.1131.el7, kernel-rt-debug-devel-3.10.0-1160.rt56.1131.el7 +4
- Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt-3.10.0-1160.rt56.1131.el7, kernel-rt-debug-3.10.0-1160.rt56.1131.el7, kernel-rt-debug-devel-3.10.0-1160.rt56.1131.el7 +7
Show 2 more Red Hat advisories
- RHSA-2020:1769 Released 2020-04-28 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder (v. 8) kernel-tools-libs-devel-4.18.0-193.el8
- Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-193.el8, kernel-4.18.0-193.el8, kernel-abi-whitelists-4.18.0-193.el8 +19
- RHSA-2020:1567 Released 2020-04-28 · Red Hat rating Importantkernel-rt security, bug fix, and enhancement update
- Red Hat Enterprise Linux Real Time (v. 8) kernel-rt-4.18.0-193.rt13.51.el8, kernel-rt-core-4.18.0-193.rt13.51.el8, kernel-rt-debug-4.18.0-193.rt13.51.el8 +7
- Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt-4.18.0-193.rt13.51.el8, kernel-rt-core-4.18.0-193.rt13.51.el8, kernel-rt-debug-4.18.0-193.rt13.51.el8 +9
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 5 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise MRG 2 | Affected | No fix planned: Will not fix |
| Red Hat CodeReady Linux Builder (v. 8) | Fixed | RHSA-2020:1769 |
| Red Hat Enterprise Linux BaseOS (v. 8) | Fixed | RHSA-2020:1769 |
| Red Hat Enterprise Linux Client (v. 7) | Fixed | RHSA-2020:4060 |
| Red Hat Enterprise Linux Client Optional (v. 7) | Fixed | RHSA-2020:4060 |
| Red Hat Enterprise Linux ComputeNode (v. 7) | Fixed | RHSA-2020:4060 |
| Red Hat Enterprise Linux ComputeNode Optional (v. 7) | Fixed | RHSA-2020:4060 |
| Red Hat Enterprise Linux Real Time (v. 8) | Fixed | RHSA-2020:1567 |
| Red Hat Enterprise Linux Real Time for NFV (v. 8) | Fixed | RHSA-2020:1567 |
| Red Hat Enterprise Linux Server (v. 7) | Fixed | RHSA-2020:4060 |
| Red Hat Enterprise Linux Server Optional (v. 7) | Fixed | RHSA-2020:4060 |
| Red Hat Enterprise Linux Workstation (v. 7) | Fixed | RHSA-2020:4060 |
| Red Hat Enterprise Linux Workstation Optional (v. 7) | Fixed | RHSA-2020:4060 |
| Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) | Fixed | RHSA-2021:0354 |
| Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) | Fixed | RHSA-2021:0354 |
| Red Hat Enterprise Linux for Real Time (v. 7) | Fixed | RHSA-2020:4062 |
| Red Hat Enterprise Linux for Real Time for NFV (v. 7) | Fixed | RHSA-2020:4062 |
Timeline
- 2026-10-02 Threatist record created from CVE-2020-1749
- 2026-10-03 Alias added: GHSA-pw98-cq7c-645p
References
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2020-1749 · CVE Program
- CVE-2020-1749 · NVD
- FIRST EPSS
- GHSA-pw98-cq7c-645p · GitHub Advisory Database · CC BY 4.0
- CVE-2020-1749 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences