Improper Certificate Validation in S2OPC
Noroxi assessment
Priority: Monitor (action score 29/100)
- 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: 0.19% (FIRST EPSS).
- 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.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: Systerel S2OPC 1.7.3.
Low priority for now. Upgrade to Systerel S2OPC 1.7.3 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
Improper comparison with the certificates trusted list in S2OPC allows an attacker well-formed untrusted certificate to be considered trusted
- Published
- Jun 10, 2026
- Updated
- Jun 17, 2026
- EPSS
- 0.1% · 8th percentile
- CWE
- CWE-295
Report tools
Action score
29
Monitor
Low priority for now.
- CVSS
- 29 / 40 · 7.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · GitLab
- 7.3
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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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.
We use this product, ask for helpAffected 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.
—
Check your site's encryption
This vulnerability is about certificate validation or weak cryptography. The free SSL checker tests your certificate, enabled TLS versions and weak ciphers.
Run the SSL checkVersions reported by the vendor
Affected version ranges reported by the assigning authority (GitLab). Independent of NVD's CPE analysis and usually ahead of it.
Systerel S2OPC
- 1.5.0 and later · before 1.7.3affected · semver
Same product
systerel: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-90782S2OPC through 1.7.3 NULL Pointer Dereference in alloc_notification_message_items()24Monitor
- CVE-2026-18257Improper Certificate Validation in S2OPC22Monitor
- CVE-2026-6899Improper Check for Certificate Revocation in S2OPC22Monitor
Published before and after this one in the same product
- Later →CVE-2026-18790Aug 4, 2026 · Systerel S2OPC DeleteMonitoredItemsRequest state_machine.c out-of-bounds7Monitor
- Later →CVE-2026-78049Aug 22, 2026 · Systerel S2OPC AddNodes Service sopc_node_mgt_helper_internal.c out-of-bounds11Monitor
- Later →CVE-2026-82618Aug 31, 2026 · Systerel S2OPC String Array Range Writing sopc_builtintypes.c set_range_matrix_on_string_array out-of-bounds21Monitor
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 |
|---|---|---|
| Systerel S2OPC | 1.7.3 | Vendor (CNA) |
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.
- Systerelfinder
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-1825749 days apartImproper Certificate Validation in S2OPC22Monitor
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
- low · data or configuration can be modified
- Availability
- low · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- Low
- Availability impact
- Low
Weakness class (CWE)
CWE-295 · Improper Certificate ValidationCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
nvd-secondary
Root cause
A certificate validation error is silently swallowed instead of terminating the connection. Often, code added for a test environment makes its way into production.
The bug in code
The whole CWE-295 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
override fun checkServerTrusted(chain: Array<X509Certificate>, type: String) { // Left empty for the test environment}Fixed
val client = OkHttpClient.Builder() .certificatePinner( CertificatePinner.Builder() .add("api.sirius.example", "sha256/…") .build() ).build()Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.