CVE-2026-10536

CRITICALPre-NVD 9.89.8
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-03. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: CISA-ADP (Vulnrichment) CVSS v3.1, EPSS, GitHub Security Advisory
Trending — 4 sources updated this weekElevated
9.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 9.8Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

A use-after-free vulnerability exists in libcurl when an application configures an HTTP/2 stream-dependency tree via CURLOPT_STREAM_DEPENDS or CURLOPT_STREAM_DEPENDS_E, subsequently invokes curl_easy_reset(), and finally terminates the handle with curl_easy_cleanup(). During this final cleanup phase, libcurl attempts to access and modify an internal structure that was already freed during the reset operation.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
75
EG Risk 75/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.6%
EPSS %ILE
47th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-18). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 3, 2026

Last Modified

September 15, 2026

Advisory Details (3)

Auto-updated Oct 20, 2026
Patch available.
Web page

curl - HTTP/2 stream-dependency tree UAF - CVE-2026-10536

https://curl.se/docs/CVE-2026-10536.html

Patch Availability(4)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntulibcurl4-openssl-dev (7.68.0-1ubuntu2.25+esm5) @ focal2026-10-16ubuntu
redhatcurl-0:8.12.1-4.el10_2.72026-10-12redhat
redhatlibcurl-1.dll2026-08-19redhat
redhatcurl-main-8.21.0-0.1.1.hum12026-07-17redhat

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:v3.23(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.88.0 up to 8.22.0-r0: fixed in 8.22.0-r0
—
Alpine:v3.24(1)
PackageVulnerable rangeFix by version rangeDependents
curl—
  • 7.88.0 up to 8.21.0-r0: fixed in 8.21.0-r0
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
curl7.88.1-10 ... 8.9.1-2~bpo12+1 (184 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
curl8.14.1-2 ... 8.23.0~rc2-1+exp1 (84 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
curl8.14.1-2 ... 8.21.0~rc1-1+exp1 (59 versions)
  • every version up to 8.21.0~rc2-1: fixed in 8.21.0~rc2-1
—

Weakness Classification(1)

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

Additional Vendor Advisories

(2)

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 25× in last 7d / 55× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 646 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 546 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  2. 2026-10-19 13:22 UTCEG score recompute
  3. 2026-10-19 13:22 UTCVendor advisory
  4. 2026-10-19 13:21 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  5. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  6. 2026-10-18 12:45 UTCVendor advisory
  7. 2026-10-18 12:44 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  8. 2026-10-18 05:08 UTCEG score recompute
  9. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  10. 2026-10-17 13:55 UTCEG score recompute
  11. 2026-10-17 13:55 UTCVendor advisory
  12. 2026-10-17 13:55 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  14. 2026-10-16 15:04 UTCEG score recompute
  15. 2026-10-16 15:04 UTCVendor advisory
  16. 2026-10-16 15:04 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  17. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  18. 2026-10-15 16:13 UTCEG score recompute
  19. 2026-10-15 16:13 UTCVendor advisory
  20. 2026-10-15 16:13 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  21. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  22. 2026-10-14 10:17 UTCEG score recompute
  23. 2026-10-14 10:17 UTCVendor advisory
  24. 2026-10-14 10:17 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  25. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
Show 75 more
  1. 2026-10-13 08:44 UTCVendor advisory
  2. 2026-10-13 08:44 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  3. 2026-10-12 16:39 UTCEG score recompute
  4. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  5. 2026-10-12 09:52 UTCVendor advisory
  6. 2026-10-12 09:52 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  7. 2026-10-11 20:15 UTCEG score recompute
  8. 2026-10-11 18:27 UTCEG score recompute
  9. 2026-10-11 15:01 UTCEG score recompute
  10. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  11. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  12. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  13. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  14. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  15. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  16. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  17. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  18. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  19. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  20. 2026-09-30 15:02 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  21. 2026-09-29 15:20 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  22. 2026-09-28 13:50 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  23. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  24. 2026-09-23 13:47 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  25. 2026-09-23 11:04 UTCVendor advisory
  26. 2026-09-23 11:04 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  27. 2026-09-23 06:36 UTCEG score recompute
  28. 2026-09-23 06:36 UTCVendor advisory
  29. 2026-09-23 06:36 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  30. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  31. 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  32. 2026-09-18 10:12 UTCVendor advisory
  33. 2026-09-18 10:12 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  34. 2026-09-18 06:13 UTCEG score recompute
  35. 2026-09-18 06:13 UTCVendor advisory
  36. 2026-09-18 06:13 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  37. 2026-09-16 05:14 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  38. 2026-09-15 07:26 UTCVendor advisory
  39. 2026-09-15 07:26 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  40. 2026-09-15 06:39 UTCEG score recompute
  41. 2026-09-15 06:39 UTCVendor advisory
  42. 2026-09-15 06:39 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  43. 2026-09-14 07:55 UTCVendor advisory
  44. 2026-09-14 07:55 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  45. 2026-09-14 04:00 UTCVendor advisory
  46. 2026-09-14 04:00 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  47. 2026-09-14 00:05 UTCVendor advisory
  48. 2026-09-14 00:05 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  49. 2026-09-13 16:54 UTCEG score recompute
  50. 2026-09-13 16:54 UTCVendor advisory
  51. 2026-09-13 16:54 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  52. 2026-09-13 16:46 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  53. 2026-09-13 12:52 UTCVendor advisory
  54. 2026-09-13 12:52 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  55. 2026-09-13 08:58 UTCEG score recompute
  56. 2026-09-13 08:58 UTCVendor advisory
  57. 2026-09-13 08:58 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  58. 2026-09-12 15:00 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  59. 2026-09-12 14:06 UTCEG score recompute
  60. 2026-09-12 14:06 UTCVendor advisory
  61. 2026-09-12 14:06 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  62. 2026-09-11 14:52 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  63. 2026-09-11 09:36 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  64. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  65. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  66. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  67. 2026-09-06 14:18 UTCEG score recompute
  68. 2026-09-06 14:18 UTCVendor advisory
  69. 2026-09-06 14:18 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  70. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  71. 2026-09-06 04:52 UTCVendor advisory
  72. 2026-09-06 04:52 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8
  73. 2026-09-05 23:50 UTCEG score recompute
  74. 2026-09-05 23:50 UTCVendor advisory
  75. 2026-09-05 23:50 UTCGHSA enrichmentGHSA-wjq8-x4qm-6mmh · GitHub severity CRITICAL · GitHub CVSS 9.8

Frequently asked(5)

What is CVE-2026-10536?
CVE-2026-10536 is a critical-severity vulnerability; its CVE record was published on July 3, 2026. A use-after-free vulnerability exists in libcurl when an application configures an HTTP/2 stream-dependency tree via CURLOPTSTREAMDEPENDS or CURLOPTSTREAMDEPENDSE, subsequently invokes curleasy_reset(), and finally terminates the handle with curleasycleanup(). During this final cleanup phase,…
When was the CVE record for CVE-2026-10536 published?
The CVE record for CVE-2026-10536 was published on July 3, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of September 15, 2026; the record at its source may have been updated since.
Is CVE-2026-10536 actively exploited?
CVE-2026-10536 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (47th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-10536?
CVE-2026-10536 has a CVSS v3.1 base score of 9.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-10536?
A fix for CVE-2026-10536 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-10536 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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