CyberSecBulletin
CVE-2026-100871NVD status: Deferred

Sylius: Improper Authentication

CVE-2026-100871 is a high-severity improper authentication vulnerability in Sylius, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 1.12.25, 1.13.17, 1.14.20 as the first without the flaw, so updating Sylius to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.31% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Sylius to 1.12.25 or 1.13.17 or 1.14.20 or 2.1.16, whichever matches your release line, or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
SyliusSylius1.11.0 up to, but not including, 1.12.25; 1.13.0 up to, but not including, 1.13.17; 1.14.0 up to, but not including, 1.14.20; 2.0.0 up to, but not including, 2.1.16; 2.2.0 up to, but not including, 2.2.91.12.25, 1.13.17, 1.14.20, 2.1.16, 2.2.9

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (vulncheck.com)
CVSS 3.18.8HighCNA (vulncheck.com)

Official description

Sylius versions before 1.12.25, 1.13.17, 1.14.20, 2.1.16, and 2.2.9 fail to include firewall identification in JWT tokens issued by separate Admin and Shop API endpoints. Attackers can register a shop customer account using an administrator's email address and obtain a token that the Admin API resolves to that administrator, granting full administrative access.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

How developers prevent this class of flaw

  • Use an authentication framework or library such as the OWASP ESAPI Authentication feature.

More Improper Authentication vulnerabilities (CWE-287)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Sylius

All Sylius vulnerabilities

Recent Improper Authentication vulnerabilities

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