Medium Logic error

CVE-2026-31824 — Sylius has a Promotion Usage Limit Bypass via Race Condition

Sylius is an Open Source eCommerce Framework on Symfony. A Time-of-Check To Time-of-Use (TOCTOU) race condition was discovered in the promotion usage limit enforcement. The same class of vulnerability affects the promotion usage limit (the global used counter on Promotion entities), coupon usage limit (the global used counter on PromotionCoupon entities), and coupon per-customer usage limit (the per-customer redemption count on PromotionCoupon entities). In all three cases, the eligibility check reads the used counter (or order count) from an in-memory Doctrine entity during validation, while the actual usage increment in OrderPromotionsUsageModifier happens later during order completion — with no database-level locking or atomic operations between the two phases. Because Doctrine flushes an absolute value (SET used = 1) rather than an atomic increment (SET used = used + 1), and because the affected entities lack optimistic locking, concurrent requests all read the same stale usage counts and pass the eligibility checks simultaneously. An attacker can exploit this by preparing multiple carts with the same limited-use promotion or coupon and firing simultaneous PATCH /api/v2/shop/orders/{token}/complete requests. All requests pass the usage limit checks and complete successfully, allowing a single-use promotion or coupon to be redeemed an arbitrary number of times. The per-customer limit can be bypassed in the same way by a single customer completing multiple orders concurrently. No authentication is required to exploit this vulnerability. This may lead to direct financial loss through unlimited redemption of limited-use promotions and discount coupons. The issue is fixed in versions: 1.9.12, 1.10.16, 1.11.17, 1.12.23, 1.13.15, 1.14.18, 2.0.16, 2.1.12, 2.2.3 and above.

Published Mar 10, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.3% (30-day exploitation probability)+3
Technical severity (medium)+3
Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.31%

ahead of 23% of scored CVEs · Oct 15, 2026

Affects

Sylius

CVSS base

5.9

Medium · 3 source(s)

Prioritization reference: 8.2 provisional

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

Yes

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

Documented mitigation — github.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Sylius Sylius).
The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
Apply the documented mitigations until a definitive fix is available.
Search available logs for exploit probes matching the vulnerability class (logic error), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Sylius	Sylius	version >= 2.2.0, < 2.2.3version < 1.9.12version >= 1.10.0, < 1.10.16version >= 1.11.0, < 1.11.17version >= 1.12.0, < 1.12.23version >= 1.13.0, < 1.13.15version >= 1.14.0, < 1.14.18version >= 2.0.0, < 2.0.16 and 1 more version >= 2.1.0, < 2.1.12	Vulnerable	CVE Program (cve.org) e CISA ADP
Sylius	Sylius	< 1.9.12≥ 2.2.0 and < 2.2.3≥ 2.1.0 and < 2.1.12≥ 2.0.0 and < 2.0.16≥ 1.14.0 and < 1.14.18≥ 1.13.0 and < 1.13.15≥ 1.12.0 and < 1.12.23≥ 1.11.0 and < 1.11.17 and 1 more ≥ 1.10.0 and < 1.10.16	Vulnerable	NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

High

Privileges required

None

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
8.2	CVSS 3.1	High	3.9	4.2	security-advisories@github.com via NIST National Vulnerability Database
8.2	CVSS 3.1	High	—	—	GitHub_M via CVE Program (cve.org) e CISA ADP
5.9	CVSS 3.1	Medium	2.2	3.6	nvd@nist.gov via NIST National Vulnerability Database

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N (score shown at the top: nvd@nist.gov)

Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 8.2 (security-advisories@github.com via NIST National Vulnerability Database) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-367 · TOCTOU Race Condition

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.31%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).

web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

2026
Affected products added · sylius/sylius
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
Fix documented
Oct 13, 2026 · NIST National Vulnerability Database
CVSS changed · 5.9
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Mar 10, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

github.com/Sylius/Sylius/security/advisories/GHSA-7mp4-25j8-hp5q
Mitigation, Vendor Advisory, x_refsource_CONFIRM, NIST National Vulnerability Database

Elsewhere on this site

Sylius
every CVE for this vendor

Logic error
same class

CWE-367
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-108724 Sylius through 2.3.0 Authorization Bypass via Shop API Product-Review Endpoint 4d
High CVE-2026-100872 Sylius 2.x before 2.1.16 and 2.2.9 Payment Amount Overwrite 18d
Medium CVE-2026-100869 Sylius 2.x before 2.1.16 and 2.2.9 Arbitrary Payment Action via Shop API 18d
High CVE-2026-100871 Sylius before 1.12.25, 1.13.17, 1.14.20, 2.1.16, and 2.2.9 JWT Audience Confusion Allows Admin API Authentication 18d
High CVE-2026-100870 Sylius before 1.12.25, 1.13.17, 1.14.20, 2.1.16, and 2.2.9 Admin Password Reset Poisoning via Host Header 18d
Medium CVE-2026-53638 Sylius: Channel-based payment method restriction bypass on shop account orders API endpoint Sep 8, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-31824 is "Sylius has a Promotion Usage Limit Bypass via Race Condition", rated Medium. It affects Sylius (Sylius); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.9 describes technical severity. EPSS 0.31% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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