An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products.
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.
- Published
- Dec 11, 2020
- Updated
- Jun 16, 2026
- EPSS
- 2.8% · 86th percentile
- CWE
- CWE-787
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Report tools
Action score
33
Monitor
Low priority for now.
- CVSS
- 32 / 40 · 8.2 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 2.8%
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| uip project | uip | cpe:2.3:a:uip_project:uip |
| contiki-os | contiki | cpe:2.3:o:contiki-os:contiki |
| open-iscsi project | open-iscsi | cpe:2.3:a:open-iscsi_project:open-iscsi |
| siemens | sentron 3va com100 firmware | cpe:2.3:o:siemens:sentron_3va_com100_firmware |
| siemens | sentron 3va com100 | cpe:2.3:h:siemens:sentron_3va_com100 |
| siemens | sentron 3va com800 firmware | cpe:2.3:o:siemens:sentron_3va_com800_firmware |
| siemens | sentron 3va com800 | cpe:2.3:h:siemens:sentron_3va_com800 |
| siemens | sentron 3va dsp800 firmware | cpe:2.3:o:siemens:sentron_3va_dsp800_firmware |
| siemens | sentron 3va dsp800 | cpe:2.3:h:siemens:sentron_3va_dsp800 |
| siemens | sentron pac2200 clp firmware | cpe:2.3:o:siemens:sentron_pac2200_clp_firmware |
| siemens | sentron pac2200 clp | cpe:2.3:h:siemens:sentron_pac2200_clp |
| siemens | sentron pac2200 firmware | cpe:2.3:o:siemens:sentron_pac2200_firmware |
and 9 more
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- open-iscsi project open-iscsiup to 2.1.7 inclusive
- siemens sentron 3va com100 firmwarebefore 4.4.1
- siemens sentron 3va com800 firmwarebefore 4.4.1
- siemens sentron 3va dsp800 firmwarebefore 4.0
- siemens sentron pac2200 clp firmwareall versions
- siemens sentron pac2200 firmwarebefore 3.2.2
- siemens sentron pac3200 firmwarebefore 2.4.7
- siemens sentron pac3200t firmwarebefore 3.2.2
- siemens sentron pac3220 firmwarebefore 3.2.0
- siemens sentron pac4200 firmwarebefore 2.3.0
- uip project uipup to 1.0 inclusive
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | open-iscsi | before 2.1.3-1 | 2.1.3-1 |
| openSUSE:Tumbleweed | open-iscsi | before 2.1.5-80.2 | 2.1.5-80.2 |
| SUSE:Linux Enterprise Module for Basesystem 15 SP2 | open-iscsi | before 2.1.4-22.14.1 | 2.1.4-22.14.1 |
| SUSE:Linux Enterprise Module for Legacy 15 SP2 | open-iscsi | before 2.0.876-13.42.1 | 2.0.876-13.42.1 |
| SUSE:Linux Enterprise Server 12 SP2-BCL | open-iscsi | before 2.0.873-46.17.2 | 2.0.873-46.17.2 |
| SUSE:Linux Enterprise Server 12 SP3-BCL | open-iscsi | before 2.0.876-53.34.1 | 2.0.876-53.34.1 |
| SUSE:OpenStack Cloud 9 | open-iscsi | before 2.0.876-12.27.2 | 2.0.876-12.27.2 |
Same product
uip project: all recordsOther highest-scoring records for the same primary product.
- CVE-2020-17438An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products.45Plan
- CVE-2020-17439An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products.34Monitor
- CVE-2020-17440An issue was discovered in uIP 1.0, as used in Contiki 3.0 and other products.31Monitor
- CVE-2020-13987An issue was discovered in Contiki through 3.0.31Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:open-iscsi | 2.1.3-1 · Debian:12 | Package registry (OSV) |
| opensuse:open-iscsi | 2.1.5-80.2 · openSUSE:Tumbleweed | Package registry (OSV) |
| suse:open-iscsi | 2.1.4-22.14.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP2 | Package registry (OSV) |
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.
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 researchersFinders, 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).
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
- low · data can be read
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-787 · Out-of-bounds WriteCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
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.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- cert-portal.siemens.com/productcert/pdf/ssa-541018.pdf
- us-cert.cisa.gov/ics/advisories/icsa-20-343-01
- www.kb.cert.org/vuls/id/815128
Vendor advisories and official records. Exploit/PoC links are deliberately left out.