cve.bz

CVE-2026-128042 OpenMage magento-lts before 20.19.0 Race Condition in Coupon Usage Limits

6.3 mediumEPSS 0.3%

Medium (6.3) in openmage magento-lts. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.

On this page
OpenMage magento-lts before 20.19.0 and 21.0.0-beta1 before 21.0.0-beta3 contains a race condition in shopping cart price rule usage limits, because Mage_SalesRule_Model_Validator checks coupon limits without locking and the usage counters are later incremented non-atomically. Unauthenticated attackers, including guest shoppers, can submit concurrent checkouts to redeem a limited coupon more times than its cap allows.

Severity

CVSS 4.0

6.3 medium
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

3.7 low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS
0.3% estimated probability of exploitation activity in the next 30 days; 21st percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWE
CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)
OWASP Top 10
A06:2025 Insecure Design
Published
Modified
Assigned by
VulnCheck (CNA)
NVD analysis
Deferred: the NVD does not plan to analyze it
Record from
the NVD, synced

Ask an AI about this CVE

ChatGPTClaudeGoogle AI Mode

Show the promptExplain CVE-2026-128042 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-128042?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-128042?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-128042 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.

Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.

Badge for a README or a site

CVE-2026-128042

An image that stays current: it is drawn from the data each time it is fetched (a host that proxies images, as GitHub does, may show its copy for a while). Markdown:

[![CVE-2026-128042](https://cve.bz/cve/badge/CVE-2026-128042.svg)](https://cve.bz/cve/CVE-2026-128042)

HTML:

<a href="https://cve.bz/cve/CVE-2026-128042"><img src="https://cve.bz/cve/badge/CVE-2026-128042.svg" alt="CVE-2026-128042"></a>

Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
OpenMage magento-ltsbefore 20.19.0
OpenMage magento-ltsfrom 21.0.0-beta1 before 21.0.0-beta3

Attack patterns (CAPEC)

  • CAPEC-26 Leveraging Race Conditions Likelihood: High · Severity: High
  • CAPEC-29 Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions Likelihood: High · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

History

  1. The NVD deferred its analysis

Changes since this site first stored the record. The same for every record: /api/public/changes.

References

Check your stackJSON