CVE-2020-13987
No exploitation reported by the sources we read.
- Published2020-12-11
- WeaknessCWE-125
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
An issue was discovered in Contiki through 3.0. An Out-of-Bounds Read vulnerability exists in the uIP TCP/IP Stack component when calculating the checksums for IP packets in upper_layer_chksum in net/ipv4/uip.c.
Timeline
dates in UTC- 2020-12-1122:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-13987?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-13987?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 2.1 | ≤ 2.1.12 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 4.4 | < 4.4.1 | 4.4.1 | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 4.4 | < 4.4.1 | 4.4.1 | NVD |
3 more products in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Vendor advisories
Siemens TCP/IP Stack Vulnerabilities-AMNESIA:33 in SENTRON PAC / 3VA Devices (Update C)
SENTRON 3VA COM100/800 · SENTRON PAC3200 · SENTRON PAC4200
Multiple Embedded TCP/IP Stacks
uIP (EOL): Version 1.0 and prior · uIP-Contiki-NG: Version 4.5 and prior · Nut/Net: Version 5.1 and prior · +5 more
Fix
- Vendor fix CISA ICSA-21-068-06 · 1 productUpdate to V4.4.1 or later version
- Vendor fix CISA ICSA-21-068-06 · 1 productUpdate to V2.4.7 or later version
- Vendor fix CISA ICSA-21-068-06 · 1 productUpdate to V2.3.0 or later version
- Vendor fix CISA ICSA-20-343-01 · 8 productsAdditional vendors affected by the reported vulnerabilities have also released security advisories related to their affected products. Those advisories are as follows:
- Mitigation from the vendor CISA ICSA-21-068-06 · 3 productsFor successful exploitation, an attacking system must be located in the same Modbus TCP segment as a vulnerable device. Therefore ensure that only trusted systems are attached to that segment and only trusted persons have access.
Advisories and patches
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
- NVDCVSS 3.17.5read 2026-10-23
- NVDCVSS 2.05read 2026-10-23
- NVDweakness (CWE)CWE-125read 2026-10-23
- FIRST EPSSEPSS score3.3 %2026-10-22
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- 2020-12-11
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2020-13987?
Is CVE-2020-13987 actively exploited?
What is the CVSS score for CVE-2020-13987?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.