CVE-2026-8458

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

Score 6.5 from GitHub Security Advisory published 2026-07-03. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 4 sources updated this weekElevated
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: Elevated riskExposed: 0

A fix is available — apply it.

libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services".

libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead.

When reusing a connection a range of criteria must be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different services.

CVSS v3
6.5
EG Score
6.5(medium)
EG Risk
45(Track)
EG Risk 45/100SSVC: 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
Severity65% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
31%
KEV
Not listed

Published

July 3, 2026

Last Modified

September 15, 2026

Advisory Details (3)

Auto-updated Jul 8, 2026
No patch confirmed yet.
generic

HackerOne

https://hackerone.com/reports/3721183
generic
https://curl.se/docs/CVE-2026-8458.json
generic

curl - wrong reuse for different services - CVE-2026-8458

https://curl.se/docs/CVE-2026-8458.html

Vendor Advisories for CVE-2026-8458(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 (7.58.0-2ubuntu3.24+esm9) @ bionic2026-09-18ubuntu
redhatpatch2026-08-19redhat
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 21× in last 7d / 65× 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 221 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-8458?
CVE-2026-8458 is a medium vulnerability published on July 3, 2026. libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services". libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead. When…
When was CVE-2026-8458 disclosed?
CVE-2026-8458 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-2026-8458 actively exploited?
CVE-2026-8458 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 69.0% of all scored CVEs.
What is the CVSS score of CVE-2026-8458?
CVE-2026-8458 has a CVSS v3.1 base score of 6.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-8458?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-8458, 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-2026-8458

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