CVE-2026-48747

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under NVD CVSS v3. 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, nvd
5.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.3Exploit: NoneExposed: 0

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

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 7.4.13 and 8.0.13, MailomatRequestParser::validateSignature() parsed X-MOM-Webhook-Signature as algo=signature and passed the request-selected algorithm to hash_hmac(), allowing a signature algorithm downgrade instead of enforcing Mailomat's documented SHA-256 webhook signature. This issue is fixed in versions 7.4.13 and 8.0.13.

CVSS v3
5.3
EG Score
5.3(medium)
EPSS
9.8%
KEV
Not listed

Published

June 15, 2026

Last Modified

July 15, 2026

Advisory Details (4)

Auto-updated Jul 19, 2026
Patch available. Sources: github_commit, github_release, github.
github Patch Available

Mailomat Mailer Webhook Parser Reads the HMAC Algorithm from the Request: Signature Algorithm Downgrade · Advisory · symfony/symfony · GitHub

https://github.com/symfony/symfony/security/advisories/GHSA-rrj9-5q2j-4gvr
github_release Patch Available

v8.0.13

Patch available: symfony/symfony v8.0.13

https://github.com/symfony/symfony/releases/tag/v8.0.13
github_release Patch Available

v7.4.13

Patch available: symfony/symfony v7.4.13

https://github.com/symfony/symfony/releases/tag/v7.4.13
github_commit Patch Available

commit bdfe9fe0d94d (symfony/symfony)

Patch available: symfony/symfony v7.4.13 (contains commit bdfe9fe0d94d)

https://github.com/symfony/symfony/commit/bdfe9fe0d94d33dfaca0bc2fe0b00b54767b0c88

Vendor Advisories for CVE-2026-48747(1)

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

Affected Packages

(2 across 1 ecosystem)
Packagist(2)
PackageVulnerable rangeFixed inDependents
symfony/mailomat-mailerv8.0.08.0.13—
symfony/symfonyv8.0.0 ... v8.0.9 (13 versions)8.0.13—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 13× 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. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-21 15:25 UTCEPSS rescore
  3. 2026-07-20 17:08 UTCEPSS rescore
  4. 2026-07-19 14:31 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-19 02:29 UTCEPSS rescore
  7. 2026-07-18 10:04 UTCEPSS rescore
  8. 2026-07-16 17:03 UTCEPSS rescore
  9. 2026-07-15 19:48 UTCEG score recompute▼ 1.00
  10. 2026-07-15 16:57 UTCEPSS rescore
  11. 2026-07-15 16:23 UTCNVD updateCVSS v3 → 5.3
  12. 2026-07-14 19:34 UTCEG score recompute▲ 6.30
  13. 2026-07-14 19:31 UTCMITRE cvelistV5CVSS v3 → 6.3 · CVSS v4 → 6.3
  14. 2026-06-15 17:45 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-48747?
CVE-2026-48747 is a medium vulnerability published on June 15, 2026. Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 7.4.13 and 8.0.13, MailomatRequestParser::validateSignature() parsed X-MOM-Webhook-Signature as algo=signature and passed the request-selected algorithm to hash_hmac(), allowing a signature…
When was CVE-2026-48747 disclosed?
CVE-2026-48747 was first published in the National Vulnerability Database on June 15, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-48747 actively exploited?
CVE-2026-48747 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 9.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-48747?
CVE-2026-48747 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-48747?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-48747, 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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