CVE-2026-49858

MEDIUMPre-NVD 5.95.9—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 90% of all CVEs by exploit prediction. 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).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.9
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.9Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

API Platform Core is a system to create hypermedia-driven REST and GraphQL APIs. In versions from 2.6.0 prior to 4.1.29, 4.2.26, and 4.3.12, a missing isCacheKeySafe gate in the JSON:API and HAL item normalizers causes a cross-user attribute leak. #[ApiProperty(security: ...)] is evaluated per request to decide whether a property is exposed. The componentsCache arrays in ApiPlatform\JsonApi\Serializer\ItemNormalizer and ApiPlatform\Hal\Serializer\ItemNormalizer are keyed on $context['cache_key'], which is set unconditionally before delegating to the parent normalizer. The component structure (attributes, relationships, links) computed for one request can therefore be reused for a subsequent request whose user has a different set of accessible properties. A user with lower privileges may end up seeing the structure of properties that the security predicate would otherwise have hidden for them. This issue has been fixed in versions 4.1.29, 4.2.26, and 4.3.12.

CVSS v3
5.9
EG Score
5.9(medium)
EPSS
9.6%
KEV
Not listed

Published

July 1, 2026

Last Modified

July 2, 2026

Advisory Details (1)

Auto-updated Jul 3, 2026
Patch available. Sources: github.
github Patch Available

Cross-user attribute leak in JSON:API and HAL item normalizers due to missing isCacheKeySafe gate · Advisory · api-platform/core · GitHub

https://github.com/api-platform/core/security/advisories/GHSA-pjhx-3c3w-9v23

Vendor Advisories for CVE-2026-49858(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(3 across 1 ecosystem)
Packagist(3)
PackageVulnerable rangeFixed inDependents
api-platform/core4.1.14 ... v4.1.9 (230 versions)4.1.29—
api-platform/hal—4.1.29—
api-platform/json-api4.1.14 ... v4.1.9 (55 versions)4.1.29—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 13× in last 7d / 19× 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.

  1. 2026-07-11 08:27 UTCEPSS rescore
  2. 2026-07-10 22:28 UTCEG score recompute
  3. 2026-07-09 22:19 UTCEG score recompute
  4. 2026-07-09 19:10 UTCEPSS rescore
  5. 2026-07-08 22:11 UTCEG score recompute
  6. 2026-07-08 15:16 UTCEPSS rescore
  7. 2026-07-07 22:03 UTCEG score recompute
  8. 2026-07-07 13:46 UTCEPSS rescore
  9. 2026-07-06 21:53 UTCEG score recompute
  10. 2026-07-06 16:27 UTCEPSS rescore
  11. 2026-07-06 02:23 UTCEPSS rescore
  12. 2026-07-05 21:44 UTCEG score recompute
  13. 2026-07-05 02:30 UTCEPSS rescore
  14. 2026-07-04 21:35 UTCEG score recompute
  15. 2026-07-04 06:31 UTCEPSS rescore
  16. 2026-07-03 21:26 UTCEG score recompute
  17. 2026-07-02 21:17 UTCEG score recompute
  18. 2026-07-01 21:08 UTCEG score recompute
  19. 2026-07-01 21:08 UTCNVD updatefirst tracked

Frequently asked(5)

What is CVE-2026-49858?
CVE-2026-49858 is a medium vulnerability published on July 1, 2026. API Platform Core is a system to create hypermedia-driven REST and GraphQL APIs. In versions from 2.6.0 prior to 4.1.29, 4.2.26, and 4.3.12, a missing isCacheKeySafe gate in the JSON:API and HAL item normalizers causes a cross-user attribute leak. #[ApiProperty(security: ...)] is evaluated per…
When was CVE-2026-49858 disclosed?
CVE-2026-49858 was first published in the National Vulnerability Database on July 1, 2026, with the most recent update on July 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-49858 actively exploited?
CVE-2026-49858 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 9.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-49858?
CVE-2026-49858 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2026-49858?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-49858, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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