CVE-2026-12503 (GCVE-0-2026-12503)
Vulnerability from cvelistv5 – Published: 2026-07-24 13:57 – Updated: 2026-07-24 14:57
VLAI
EPSS
VEX
Title
Loytec LINX firmware: Improper Link Resolution in /usr/bin/larm_starter
Summary
Improper Link Resolution (CWE-59) in `/usr/bin/larm_starter` in Loytec L-INX, L-GATE, L-ROC, L-IOB, L-DALI, L-VIS and L-PAD through 8.4.16 on LINX-A64 allows an authenticated `larmapp` attacker to make `/etc/passwd` writable by the `larmapp` group (leading to root privilege escalation) via a symlink attack on `/etc/lighttpd/ssl/server.pem`.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-24 14:57 UTC
CWE
- CWE-59 - Improper link resolution before file access ('link following')
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://www.loytec.com/support/product-security/a… | vendor-advisory |
Impacted products
8 products
| Vendor | Product | Version | |
|---|---|---|---|
| Loytec | LIP-ME20xC |
Affected:
0 , ≤ 8.4.16
(custom)
|
|
| Loytec | L-INX |
Affected:
0 , ≤ 8.4.16
(custom)
|
|
| Loytec | L-GATE |
Affected:
0 , ≤ 8.4.16
(custom)
|
|
| Loytec | L-ROC |
Affected:
0 , ≤ 8.4.16
(custom)
|
|
| Loytec | L-IOB |
Affected:
0 , ≤ 8.4.16
(custom)
|
|
| Loytec | L-DALI |
Affected:
0 , ≤ 8.4.16
(custom)
|
|
| Loytec | L-VIS |
Affected:
0 , ≤ 8.4.16
(custom)
|
|
| Loytec | L-PAD |
Affected:
0 , ≤ 8.4.16
(custom)
|
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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