CVE-2026-48979

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 82% 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
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.5Exploit: NoneExposed: 0

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

PHP Standard Library (PSL) is set of APIs covering async, collections, networking, I/O, cryptography, terminal UI, etc. In versions 6.1.0, 6.1.1 and 6.2.0, the Psl\H2\ServerConnection does not validate that the total bytes received in DATA frames match the content-length header declared in the HEADERS frame, allowing request smuggling. This is in violation of RFC 9113 §8.1.1. A malicious client is able to send more DATA bytes than declared, smuggling additional content past application-level size limits and send fewer DATA bytes than declared and close the stream early, causing applications that trust the declared length to behave incorrectly. The vulnerability is only reachable for consumers using Psl\H2\ServerConnection directly to accept untrusted client traffic. Consumers of documented high-level PSL APIs are not affected. This issue has been fixed in versions 6.1.2 and 6.2.1.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
18.3%
KEV
Not listed

Published

June 17, 2026

Last Modified

June 23, 2026

Advisory Details (3)

Auto-updated Jun 17, 2026
Patch available. Sources: github, github_release.
github Patch Available

HTTP/2 server-side missing content-length validation enables request smuggling · Advisory · php-standard-library/php-standard-library · GitHub

https://github.com/php-standard-library/php-standard-library/security/advisories/GHSA-pw9p-jvrm-f7rm
github_release Patch Available

Hevlaska 6.2.1

Patch available: php-standard-library/php-standard-library 6.2.1

https://github.com/php-standard-library/php-standard-library/releases/tag/6.2.1
github_release Patch Available

Hevlaska 6.1.2

Patch available: php-standard-library/php-standard-library 6.1.2

https://github.com/php-standard-library/php-standard-library/releases/tag/6.1.2

Vendor Advisories for CVE-2026-48979(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 21× in last 7d / 68× 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. 2026-07-07 00:13 UTCEG score recompute
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 12:45 UTCEG score recompute
  4. 2026-07-06 02:23 UTCEPSS rescore
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  7. 2026-07-05 02:30 UTCEPSS rescore
  8. 2026-07-05 02:22 UTCEG score recompute
  9. 2026-07-04 14:55 UTCEG score recompute
  10. 2026-07-04 06:31 UTCEPSS rescore
  11. 2026-07-04 03:28 UTCEG score recompute
  12. 2026-07-03 16:00 UTCEG score recompute
  13. 2026-07-03 04:34 UTCEG score recompute
  14. 2026-07-02 17:04 UTCEG score recompute
  15. 2026-07-02 05:37 UTCEG score recompute
  16. 2026-07-01 18:09 UTCEG score recompute
  17. 2026-07-01 15:07 UTCEPSS rescore
  18. 2026-07-01 06:43 UTCEG score recompute
  19. 2026-06-30 23:22 UTCEPSS rescore
  20. 2026-06-30 19:15 UTCEG score recompute
  21. 2026-06-30 07:48 UTCEG score recompute
  22. 2026-06-29 20:21 UTCEG score recompute
  23. 2026-06-29 14:06 UTCEPSS rescore
  24. 2026-06-29 14:06 UTCEPSS rescore
  25. 2026-06-29 08:54 UTCEG score recompute
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  1. 2026-06-28 21:27 UTCEG score recompute
  2. 2026-06-28 14:07 UTCEPSS rescore
  3. 2026-06-28 10:00 UTCEG score recompute
  4. 2026-06-28 04:56 UTCEPSS rescore
  5. 2026-06-28 04:56 UTCEPSS rescore
  6. 2026-06-27 22:33 UTCEG score recompute
  7. 2026-06-27 11:06 UTCEG score recompute
  8. 2026-06-27 03:08 UTCEPSS rescore
  9. 2026-06-26 23:39 UTCEG score recompute
  10. 2026-06-26 12:13 UTCEG score recompute
  11. 2026-06-26 00:46 UTCEG score recompute
  12. 2026-06-25 13:49 UTCEPSS rescore
  13. 2026-06-25 13:18 UTCEG score recompute
  14. 2026-06-25 01:51 UTCEG score recompute
  15. 2026-06-24 14:23 UTCEG score recompute
  16. 2026-06-24 14:05 UTCEPSS rescore
  17. 2026-06-24 02:57 UTCEG score recompute
  18. 2026-06-23 21:33 UTCEPSS rescore
  19. 2026-06-23 21:33 UTCEPSS rescore
  20. 2026-06-23 15:30 UTCEG score recompute
  21. 2026-06-23 04:03 UTCEG score recompute
  22. 2026-06-22 16:35 UTCEG score recompute
  23. 2026-06-22 14:25 UTCEPSS rescore
  24. 2026-06-22 14:25 UTCEPSS rescore
  25. 2026-06-22 05:06 UTCEG score recompute
  26. 2026-06-21 17:37 UTCEG score recompute
  27. 2026-06-21 14:56 UTCEPSS rescore
  28. 2026-06-21 14:56 UTCEPSS rescore
  29. 2026-06-21 06:08 UTCEG score recompute
  30. 2026-06-21 01:59 UTCEPSS rescore
  31. 2026-06-21 01:59 UTCEPSS rescore
  32. 2026-06-20 18:41 UTCEG score recompute
  33. 2026-06-20 07:08 UTCEG score recompute
  34. 2026-06-19 19:42 UTCEG score recompute
  35. 2026-06-19 19:26 UTCEPSS rescore
  36. 2026-06-19 19:26 UTCEPSS rescore
  37. 2026-06-19 08:15 UTCEG score recompute
  38. 2026-06-18 20:49 UTCEG score recompute
  39. 2026-06-18 17:52 UTCEPSS rescore
  40. 2026-06-18 17:52 UTCEPSS rescore
  41. 2026-06-18 09:22 UTCEG score recompute
  42. 2026-06-17 21:51 UTCEG score recompute
  43. 2026-06-17 21:51 UTCNVD updatefirst tracked

Frequently asked(5)

What is CVE-2026-48979?
CVE-2026-48979 is a high vulnerability published on June 17, 2026. PHP Standard Library (PSL) is set of APIs covering async, collections, networking, I/O, cryptography, terminal UI, etc. In versions 6.1.0, 6.1.1 and 6.2.0, the Psl\H2\ServerConnection does not validate that the total bytes received in DATA frames match the content-length header declared in the…
When was CVE-2026-48979 disclosed?
CVE-2026-48979 was first published in the National Vulnerability Database on June 17, 2026, with the most recent update on June 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-48979 actively exploited?
CVE-2026-48979 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 18.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-48979?
CVE-2026-48979 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-48979?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-48979, 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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