CVE-2026-42055

HIGHPre-NVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

Score 8.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-06-17. a secondary CVSS source baseline 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 7%CVSS: 8.1Exploit: None knownExposed: 0

A fix is available — apply it.

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability exists when the proxy_http_version to 2 or grpc_pass directives are used to proxy HTTP/2 traffic, the ignore_invalid_headers directive is set to off, and the large_client_header_buffers directive size is larger than 2 megabytes. A remote, unauthenticated attacker, along with conditions beyond their control, could send large headers while creating an upstream request. This may cause a heap-based buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS v3
8.1
EG Score
8.1(medium)
EG Risk
39(Track)
EG Risk 39/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity81% × 45%
Exploitation7% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
7%
EPSS %ILE
93%
KEV
Not listed

Published

June 17, 2026

Last Modified

September 14, 2026

Advisory Details (1)

Auto-updated Jun 18, 2026
No patch confirmed yet.
generic

myF5

https://my.f5.com/manage/s/article/K000161584

Vendor Advisories for CVE-2026-42055(11)

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

Patch Availability(10)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntunginx-light (1.28.3-2ubuntu1.6) @ resolute2026-09-14ubuntu
redhatrhui5/rhua-tp-rhel9:17872412602026-08-24redhat
redhatdiscovery/discovery-ui-rhel9:17848217502026-07-27redhat
redhatrhui5/rhua-rhel9:17847950762026-07-23redhat
redhatnginx:1.24-8100020260707171317.489197e62026-07-13redhat
redhatnginx:1.26-9080020260707110000.92026-07-08redhat
redhatnginx:1.24-9080020260707164406.92026-07-08redhat
redhatnginx-2:1.20.1-28.el9_8.42026-07-07redhat
redhatnginx-2:1.26.3-6.el10_2.52026-07-07redhat
redhatnginx-main-1.30.3-2.hum12026-06-19redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(8 across 8 ecosystems)
Alpine:v3.21(1)
PackageVulnerable rangeFixed inDependents
nginx—1.26.3-r2—
Alpine:v3.22(1)
PackageVulnerable rangeFixed inDependents
nginx—1.28.3-r4—
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
nginx—1.28.3-r4—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
nginx—1.30.3-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
nginx1.18.0-6.1 ... 1.18.0-6.1+deb11u7 (8 versions)1.18.0-6.1+deb11u8—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
nginx1.22.1-9 ... 1.22.1-9+deb12u8 (9 versions)1.22.1-9+deb12u9—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
nginx1.26.3-3 ... 1.26.3-3+deb13u6 (7 versions)1.26.3-3+deb13u7—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
nginx1.26.3-3 ... 1.30.1-4 (24 versions)1.30.1-5—

Weakness Classification(3)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 18× in last 7d / 63× 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.

Showing the most recent 100 of 350 total refreshes for this CVE.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-17 19:31 UTCEPSS rescore
  3. 2026-09-16 14:08 UTCEPSS rescore
  4. 2026-09-16 05:15 UTCEPSS rescore
  5. 2026-09-14 13:38 UTCEG score recompute
  6. 2026-09-14 13:38 UTCVendor advisory
  7. 2026-09-14 13:38 UTCGHSA enrichment
  8. 2026-09-14 12:34 UTCEG score recompute
  9. 2026-09-14 12:34 UTCVendor advisory
  10. 2026-09-14 12:34 UTCGHSA enrichment
  11. 2026-09-14 03:08 UTCEG score recompute
  12. 2026-09-14 03:08 UTCVendor advisory
  13. 2026-09-14 03:07 UTCGHSA enrichment
  14. 2026-09-13 16:47 UTCEPSS rescore
  15. 2026-09-13 14:14 UTCEG score recompute
  16. 2026-09-13 14:14 UTCVendor advisory
  17. 2026-09-13 14:14 UTCGHSA enrichment
  18. 2026-09-12 15:01 UTCEPSS rescore
  19. 2026-09-11 14:53 UTCEPSS rescore
  20. 2026-09-11 09:37 UTCEPSS rescore
  21. 2026-09-10 09:34 UTCEPSS rescore
  22. 2026-09-08 22:00 UTCEPSS rescore
  23. 2026-09-07 16:01 UTCEPSS rescore
  24. 2026-09-06 13:47 UTCEPSS rescore
  25. 2026-09-04 05:06 UTCEPSS rescore
Show 75 more
  1. 2026-09-02 14:12 UTCEPSS rescore
  2. 2026-09-01 13:54 UTCEPSS rescore
  3. 2026-09-01 04:39 UTCEPSS rescore
  4. 2026-08-30 21:21 UTCEG score recompute
  5. 2026-08-30 21:21 UTCVendor advisory
  6. 2026-08-30 21:21 UTCGHSA enrichment
  7. 2026-08-30 19:17 UTCEPSS rescore
  8. 2026-08-30 01:22 UTCEPSS rescore
  9. 2026-08-28 21:41 UTCEPSS rescore
  10. 2026-08-27 14:25 UTCEPSS rescore
  11. 2026-08-26 14:46 UTCEPSS rescore
  12. 2026-08-25 13:49 UTCEPSS rescore
  13. 2026-08-25 13:23 UTCEG score recompute
  14. 2026-08-25 13:23 UTCVendor advisory
  15. 2026-08-25 13:23 UTCGHSA enrichment
  16. 2026-08-25 12:18 UTCEG score recompute
  17. 2026-08-25 12:18 UTCVendor advisory
  18. 2026-08-25 12:18 UTCGHSA enrichment
  19. 2026-08-24 22:25 UTCEG score recompute
  20. 2026-08-24 22:25 UTCVendor advisory
  21. 2026-08-24 22:25 UTCGHSA enrichment
  22. 2026-08-24 06:52 UTCVendor advisory
  23. 2026-08-24 06:52 UTCGHSA enrichment
  24. 2026-08-23 16:45 UTCVendor advisory
  25. 2026-08-23 16:45 UTCGHSA enrichment
  26. 2026-08-23 04:21 UTCEG score recompute
  27. 2026-08-23 04:21 UTCVendor advisory
  28. 2026-08-23 04:21 UTCGHSA enrichment
  29. 2026-08-23 00:19 UTCEPSS rescore
  30. 2026-08-21 23:49 UTCEPSS rescore
  31. 2026-08-21 22:31 UTCVendor advisory
  32. 2026-08-21 22:31 UTCGHSA enrichment
  33. 2026-08-21 09:33 UTCEG score recompute
  34. 2026-08-21 09:33 UTCVendor advisory
  35. 2026-08-21 09:33 UTCGHSA enrichment
  36. 2026-08-20 22:55 UTCEPSS rescore
  37. 2026-08-20 20:43 UTCVendor advisory
  38. 2026-08-20 20:43 UTCGHSA enrichment
  39. 2026-08-20 08:14 UTCEG score recompute
  40. 2026-08-20 08:14 UTCVendor advisory
  41. 2026-08-20 08:14 UTCGHSA enrichment
  42. 2026-08-19 17:03 UTCEPSS rescore
  43. 2026-08-19 08:10 UTCEG score recompute
  44. 2026-08-19 08:10 UTCVendor advisory
  45. 2026-08-19 08:10 UTCGHSA enrichment
  46. 2026-08-18 13:48 UTCEPSS rescore
  47. 2026-08-17 13:47 UTCEPSS rescore
  48. 2026-08-17 11:02 UTCVendor advisory
  49. 2026-08-17 11:02 UTCGHSA enrichment
  50. 2026-08-16 22:39 UTCEG score recompute
  51. 2026-08-16 22:39 UTCVendor advisory
  52. 2026-08-16 22:39 UTCGHSA enrichment
  53. 2026-08-16 14:56 UTCEPSS rescore
  54. 2026-08-16 10:14 UTCEG score recompute
  55. 2026-08-16 10:14 UTCVendor advisory
  56. 2026-08-16 10:14 UTCGHSA enrichment
  57. 2026-08-16 02:14 UTCEPSS rescore
  58. 2026-08-15 21:51 UTCVendor advisory
  59. 2026-08-15 21:51 UTCGHSA enrichment
  60. 2026-08-15 09:18 UTCEG score recompute
  61. 2026-08-15 09:18 UTCVendor advisory
  62. 2026-08-15 09:18 UTCGHSA enrichment
  63. 2026-08-15 01:30 UTCEPSS rescore
  64. 2026-08-14 19:54 UTCVendor advisory
  65. 2026-08-14 19:54 UTCGHSA enrichment
  66. 2026-08-14 07:30 UTCEG score recompute
  67. 2026-08-14 07:30 UTCVendor advisory
  68. 2026-08-14 07:30 UTCGHSA enrichment
  69. 2026-08-13 22:00 UTCEPSS rescore
  70. 2026-08-13 19:06 UTCVendor advisory
  71. 2026-08-13 19:06 UTCGHSA enrichment
  72. 2026-08-13 04:49 UTCVendor advisory
  73. 2026-08-13 04:49 UTCGHSA enrichment
  74. 2026-08-12 16:25 UTCEG score recompute
  75. 2026-08-12 16:25 UTCVendor advisory

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-42055?
CVE-2026-42055 is a high vulnerability published on June 17, 2026. NGINX Plus and NGINX Open Source have a vulnerability in the ngxhttpproxyv2module and ngxhttpgrpcmodule modules. This vulnerability exists when the proxyhttpversion to 2 or grpcpass directives are used to proxy HTTP/2 traffic, the ignoreinvalidheaders directive is set to off, and the…
When was CVE-2026-42055 disclosed?
CVE-2026-42055 was first published in the National Vulnerability Database on June 17, 2026, with the most recent update on September 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-42055 actively exploited?
CVE-2026-42055 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 7% probability of exploitation in the next 30 days, which ranks it in the top 6.5% of all scored CVEs.
What is the CVSS score of CVE-2026-42055?
CVE-2026-42055 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-42055?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42055, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-42055

Explore →

Is Your Infrastructure Affected by CVE-2026-42055?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs