Cyber Resilience

CVE-2021-29661

MediumPublic PoC

Published: 02 April 2021

Published
02 April 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0042 62.3th percentile
Risk Priority 11 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-29661 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Softing Opc Toolbox. Its CVSS base score is 5.4 (Medium).

Operationally, ranked in the top 37.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Softing AG OPC Toolbox through 4.10.1.13035 allows /en/diag_values.html Stored XSS via the ITEMLISTVALUES##ITEMID parameter, resulting in JavaScript payload injection into the trace file. This payload will then be triggered every time an authenticated user browses the page containing it.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

softing
opc toolbox
≤ 4.10.1.13035

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References