Skip to main content
No exploitation reportedFix available

CVE-2020-17437

No exploitation reported by the sources we read.

  • Published2020-12-11
  • WeaknessCWE-787

Am I 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 uIP 1.0, as used in Contiki 3.0 and other products. When the Urgent flag is set in a TCP packet, and the stack is configured to ignore the urgent data, the stack attempts to use the value of the Urgent pointer bytes to separate the Urgent data from the normal data, by calculating the offset at which the normal data should be present in the global buffer. However, the length of this offset is not checked; therefore, for large values of the Urgent pointer bytes, the data pointer can point to memory that is way beyond the data buffer in uip_process in uip.c.

Timeline

dates in UTC
  1. 2020-12-1123:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-17437?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-17437?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Open-iscsi project open-iscsi
BranchAffectedFixed in
2.1≤ 2.1.7no fix published
Siemens sentron 3va com100 firmwareversion to verify
BranchAffectedFixed in
4.4< 4.4.14.4.1
Siemens sentron 3va com800 firmwareversion to verify
BranchAffectedFixed in
4.4< 4.4.14.4.1

8 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

  • ICSA-21-068-06 CISA9 known affected

    Siemens TCP/IP Stack Vulnerabilities-AMNESIA:33 in SENTRON PAC / 3VA Devices (Update C)

    SENTRON 3VA COM100/800 · SENTRON 3VA DSP800 · SENTRON PAC2200 (with CLP Approval) · +6 more

  • ICSA-20-343-01 CISA8 known affected

    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

Full record on NVD

Fix

  1. Vendor fix CISA ICSA-21-068-06 · 1 productUpdate to V4.4.1 or later version
  2. Vendor fix CISA ICSA-21-068-06 · 1 productUpdate to V4.0 or later version
  3. Vendor fix CISA ICSA-21-068-06 · 1 productMID-certified devices do not support firmware updates; V3.2.2 is contained in devices that are labeled as "M22 MID"
  4. Vendor fix CISA ICSA-21-068-06 · 1 productUpdate to V3.2.2 or later version
  5. Vendor fix CISA ICSA-21-068-06 · 1 productUpdate to V2.4.7 or later version
  6. Vendor fix CISA ICSA-21-068-06 · 1 productUpdate to V3.2.0 or later version

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 3.18.2read 2026-10-23
  • NVDCVSS 2.06.4read 2026-10-23
  • NVDweakness (CWE)CWE-787read 2026-10-23
  • FIRST EPSSEPSS score2.8 %2026-10-22

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
Published
2020-12-11
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2020-17437?

An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products. When the Urgent flag is set in a TCP packet, and the stack is configured to ignore the urgent data, the stack attempts to use the value of the Urgent pointer bytes to separate the Urgent data from the normal data, by calculating the offset at which the normal data should be present in the global buffer. However, the length of this offset is not checked; therefore, for large values of the Urgent pointer bytes, the data pointer can point to memory that is way beyond the data buffer in uip_process in uip.c.

Is CVE-2020-17437 actively exploited?

Active exploitation of CVE-2020-17437 has not been confirmed. Its EPSS score was 2.8% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-17437?

CVE-2020-17437 has a CVSS v3 base score of 8.2 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H.

Hear about the next vulnerability in your software

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, October 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database