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: 0%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
0%
EPSS %ILE
36%
KEV
Not listed

Published

July 3, 2026

Last Modified

July 7, 2026

Advisory Details (3)

Auto-updated Aug 1, 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(5)

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

Patch Availability(4)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulibcurl4-openssl-dev (7.81.0-1ubuntu1.25) @ jammy2026-08-25ubuntu
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

(5 across 5 ecosystems)
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 (174 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
curl8.14.1-2 ... 8.21.0~rc3-1+exp1 (74 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 78× in last 7d / 409× 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 565 total refreshes for this CVE.

  1. 2026-08-25 13:49 UTCEPSS rescore
  2. 2026-08-25 13:38 UTCVendor advisory
  3. 2026-08-25 13:38 UTCGHSA enrichment
  4. 2026-08-25 04:26 UTCVendor advisory
  5. 2026-08-25 04:26 UTCGHSA enrichment
  6. 2026-08-25 00:42 UTCVendor advisory
  7. 2026-08-25 00:42 UTCGHSA enrichment
  8. 2026-08-24 20:55 UTCEG score recompute
  9. 2026-08-24 20:55 UTCVendor advisory
  10. 2026-08-24 20:54 UTCGHSA enrichment
  11. 2026-08-24 14:18 UTCEPSS rescore
  12. 2026-08-24 13:54 UTCVendor advisory
  13. 2026-08-24 13:54 UTCGHSA enrichment
  14. 2026-08-24 10:13 UTCEG score recompute
  15. 2026-08-24 10:13 UTCVendor advisory
  16. 2026-08-24 10:13 UTCGHSA enrichment
  17. 2026-08-24 04:46 UTCVendor advisory
  18. 2026-08-24 04:46 UTCGHSA enrichment
  19. 2026-08-24 01:03 UTCVendor advisory
  20. 2026-08-24 01:03 UTCGHSA enrichment
  21. 2026-08-23 21:12 UTCVendor advisory
  22. 2026-08-23 21:12 UTCGHSA enrichment
  23. 2026-08-23 17:31 UTCVendor advisory
  24. 2026-08-23 17:31 UTCGHSA enrichment
  25. 2026-08-23 13:49 UTCVendor advisory
Show 75 more
  1. 2026-08-23 13:49 UTCGHSA enrichment
  2. 2026-08-23 10:08 UTCVendor advisory
  3. 2026-08-23 10:08 UTCGHSA enrichment
  4. 2026-08-23 06:26 UTCVendor advisory
  5. 2026-08-23 06:26 UTCGHSA enrichment
  6. 2026-08-23 02:41 UTCEG score recompute
  7. 2026-08-23 02:41 UTCVendor advisory
  8. 2026-08-23 02:41 UTCGHSA enrichment
  9. 2026-08-23 00:19 UTCEPSS rescore
  10. 2026-08-22 23:00 UTCVendor advisory
  11. 2026-08-22 23:00 UTCGHSA enrichment
  12. 2026-08-22 19:18 UTCVendor advisory
  13. 2026-08-22 19:18 UTCGHSA enrichment
  14. 2026-08-22 13:26 UTCVendor advisory
  15. 2026-08-22 13:26 UTCGHSA enrichment
  16. 2026-08-22 09:42 UTCVendor advisory
  17. 2026-08-22 09:42 UTCGHSA enrichment
  18. 2026-08-22 05:59 UTCEG score recompute
  19. 2026-08-22 05:59 UTCVendor advisory
  20. 2026-08-22 05:59 UTCGHSA enrichment
  21. 2026-08-21 23:49 UTCEPSS rescore
  22. 2026-08-21 22:55 UTCVendor advisory
  23. 2026-08-21 22:55 UTCGHSA enrichment
  24. 2026-08-21 19:14 UTCVendor advisory
  25. 2026-08-21 19:14 UTCGHSA enrichment
  26. 2026-08-21 15:32 UTCVendor advisory
  27. 2026-08-21 15:32 UTCGHSA enrichment
  28. 2026-08-21 11:51 UTCVendor advisory
  29. 2026-08-21 11:51 UTCGHSA enrichment
  30. 2026-08-21 08:08 UTCVendor advisory
  31. 2026-08-21 08:08 UTCGHSA enrichment
  32. 2026-08-21 04:26 UTCVendor advisory
  33. 2026-08-21 04:26 UTCGHSA enrichment
  34. 2026-08-20 23:14 UTCEG score recompute
  35. 2026-08-20 23:14 UTCVendor advisory
  36. 2026-08-20 23:14 UTCGHSA enrichment
  37. 2026-08-20 22:56 UTCEPSS rescore
  38. 2026-08-20 19:33 UTCVendor advisory
  39. 2026-08-20 19:33 UTCGHSA enrichment
  40. 2026-08-20 15:52 UTCVendor advisory
  41. 2026-08-20 15:52 UTCGHSA enrichment
  42. 2026-08-20 11:22 UTCVendor advisory
  43. 2026-08-20 11:22 UTCGHSA enrichment
  44. 2026-08-20 07:40 UTCVendor advisory
  45. 2026-08-20 07:40 UTCGHSA enrichment
  46. 2026-08-20 03:57 UTCEG score recompute
  47. 2026-08-20 03:57 UTCVendor advisory
  48. 2026-08-20 03:57 UTCGHSA enrichment
  49. 2026-08-19 17:04 UTCEPSS rescore
  50. 2026-08-19 16:29 UTCVendor advisory
  51. 2026-08-19 16:29 UTCGHSA enrichment
  52. 2026-08-19 12:32 UTCVendor advisory
  53. 2026-08-19 12:32 UTCGHSA enrichment
  54. 2026-08-19 08:29 UTCVendor advisory
  55. 2026-08-19 08:29 UTCGHSA enrichment
  56. 2026-08-19 04:46 UTCVendor advisory
  57. 2026-08-19 04:46 UTCGHSA enrichment
  58. 2026-08-19 00:56 UTCVendor advisory
  59. 2026-08-19 00:56 UTCGHSA enrichment
  60. 2026-08-18 20:52 UTCEG score recompute
  61. 2026-08-18 20:52 UTCVendor advisory
  62. 2026-08-18 20:52 UTCGHSA enrichment
  63. 2026-08-18 13:49 UTCEPSS rescore
  64. 2026-08-18 13:49 UTCEPSS rescore
  65. 2026-08-18 11:46 UTCVendor advisory
  66. 2026-08-18 11:46 UTCGHSA enrichment
  67. 2026-08-18 04:27 UTCVendor advisory
  68. 2026-08-18 04:27 UTCGHSA enrichment
  69. 2026-08-17 22:49 UTCVendor advisory
  70. 2026-08-17 22:49 UTCGHSA enrichment
  71. 2026-08-17 15:30 UTCEG score recompute
  72. 2026-08-17 15:30 UTCVendor advisory
  73. 2026-08-17 15:30 UTCGHSA enrichment
  74. 2026-08-17 13:47 UTCEPSS rescore
  75. 2026-08-17 11:48 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 July 7, 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 0% probability of exploitation in the next 30 days, which ranks it in the top 63.5% 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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