Sylius is an Open Source eCommerce Framework on Symfony. The POST /api/v2/shop/orders/{tokenValue}/items endpoint does not verify cart ownership. An unauthenticated attacker can add items to other registered customers' carts by knowing the cart tokenValue. An attacker who obtains a cart tokenValue can add arbitrary items to another customer's cart. The endpoint returns the full cart representation in the response (HTTP 201). The issue is fixed in versions: 2.0.16, 2.1.12, 2.2.3 and above.
CVE-2026-31821
This medium-severity CVE scores 5.3 under NVD CVSS v3. EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.3
- EG Score
- 5.3(low)
- EG Risk
- 28(Track)EG Risk 28/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity53% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 8%
- KEV
- Not listed
Published
March 10, 2026
Last Modified
June 17, 2026
References (1)
- security-advisories@githubhttps://github.com/Sylius/Sylius/security/advisories/GHSA-wjmg-4cq5-m8hg
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 5× in last 7d / 5× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-01 04:16 UTCEPSS rescore
- 2026-07-30 16:28 UTCEPSS rescore
- 2026-07-30 01:30 UTCEPSS rescore
- 2026-07-28 15:36 UTCEPSS rescore
- 2026-07-27 13:44 UTCEG score recompute
Related CVEs(same CWE)
Same CWE
10 shownCWE-862
- CVE-2013-3960EG 9.9CRITICAL
- CVE-2015-10143EG 9.8CRITICAL
- CVE-2016-11036EG 9.8CRITICAL
- CVE-2018-11541EG 9.8CRITICAL
- CVE-2011-4183NVD 6.5EG 9.8CRITICAL
- CVE-2018-10251EG 9.8EPSS p91CRITICAL
- CVE-2018-1217EG 9.8EPSS p99CRITICAL
- CVE-2018-0015EG 9.8CRITICAL
- CVE-2017-12582EG 9.8CRITICAL
- CVE-2017-1000056EG 9.8CRITICAL
Frequently asked(5)
What is CVE-2026-31821?
When was CVE-2026-31821 disclosed?
Is CVE-2026-31821 actively exploited?
What is the CVSS score of CVE-2026-31821?
How do I remediate CVE-2026-31821?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-31821
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