CVE-2026-8927

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-03. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 4 sources updated this weekElevated
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.1Exploit: Elevated riskExposed: 0

A fix is available — apply it.

When reusing a libcurl handle for sequential transfers driven by environment-variable proxy configuration, libcurl fails to clear the proxy authentication state between requests. Specifically, if the initial transfer authenticates against proxyA using Digest auth, a subsequent transfer routed through proxyB erroneously leaks the Proxy-Authorization: header intended solely for proxyA.

CVSS v3
9.1
EG Score
9.1(medium)
EG Risk
57(Track*)
EG Risk 57/100SSVC: 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
Severity91% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
1%
EPSS %ILE
42%
KEV
Not listed

Published

July 3, 2026

Last Modified

September 15, 2026

Advisory Details (3)

Auto-updated Sep 15, 2026
No patch confirmed yet.
generic

HackerOne

https://hackerone.com/reports/3744543
generic
https://curl.se/docs/CVE-2026-8927.json
generic

curl - env-set cross-proxy Digest auth state leak - CVE-2026-8927

https://curl.se/docs/CVE-2026-8927.html

Vendor Advisories for CVE-2026-8927(6)

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

Patch Availability(5)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulibcurl4-openssl-dev (7.35.0-1ubuntu2.20+esm20) @ trusty2026-09-18ubuntu
redhatlibcurl-1.dll2026-08-19redhat
redhatcurl-0:8.12.1-4.el10_2.42026-08-17redhat
redhatrust-main-1.96.1-1.hum12026-07-02redhat
redhatcurl-main-8.21.0-0.1.hum12026-06-24redhat

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

(6 across 6 ecosystems)
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
curl—8.22.0-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
curl—8.21.0-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
curl7.74.0-1.3 ... 8.9.1-2~bpo12+1 (219 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
curl7.88.1-10 ... 8.9.1-2~bpo12+1 (178 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
curl8.14.1-2 ... 8.22.0~rc3-1+exp1 (78 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
curl8.14.1-2 ... 8.21.0~rc1-1+exp1 (59 versions)8.21.0~rc2-1—

Weakness Classification(1)

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 31× in last 7d / 141× 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 640 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-8927?
CVE-2026-8927 is a critical vulnerability published on July 3, 2026. When reusing a libcurl handle for sequential transfers driven by environment-variable proxy configuration, libcurl fails to clear the proxy authentication state between requests. Specifically, if the initial transfer authenticates against proxyA using Digest auth, a subsequent transfer routed…
When was CVE-2026-8927 disclosed?
CVE-2026-8927 was first published in the National Vulnerability Database on July 3, 2026, with the most recent update on September 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-8927 actively exploited?
CVE-2026-8927 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 58.1% of all scored CVEs.
What is the CVSS score of CVE-2026-8927?
CVE-2026-8927 has a CVSS v3.1 base score of 9.1 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-8927?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-8927, 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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