CVE-2026-82208 - Vulnerability Details - OpenCVE

With the wolfSSL backend, when CA caching is enabled and an `CURLOPT_SSL_CTX_FUNCTION` callback replaces the trust store, libcurl can silently reinstall the cached store after the callback returns. A certificate trusted by the cached store but rejected by the callback-selected store is then incorrectly accepted.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation poc

Automatable yes

Technical Impact partial

Vendors	Products
Curl	Curl

No data.

No data.

References

Link	Providers
https://curl.se/docs/CVE-2026-82208.html
https://curl.se/docs/CVE-2026-82208.json
https://hackerone.com/reports/3973090

History

Thu, 10 Sep 2026 05:00:00 +0000

Type	Values Removed	Values Added
Weaknesses	CWE-296

Tue, 08 Sep 2026 19:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-295
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}` ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Sun, 06 Sep 2026 20:15:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-296

Sun, 06 Sep 2026 19:45:00 +0000

Type	Values Removed	Values Added
First Time appeared		Curl Curl curl
Vendors & Products		Curl Curl curl

Sun, 06 Sep 2026 18:00:00 +0000

Type	Values Removed	Values Added
Description		With the wolfSSL backend, when CA caching is enabled and an `CURLOPT_SSL_CTX_FUNCTION` callback replaces the trust store, libcurl can silently reinstall the cached store after the callback returns. A certificate trusted by the cached store but rejected by the callback-selected store is then incorrectly accepted.
Title		wolfSSL CA-cache hit overrides callback
References		https://curl.se/docs/CVE-2026-82208.html https://curl.se/docs/CVE-2026-82208.json https://hackerone.com/reports/3973090

MITRE

Status: PUBLISHED

Assigner: curl

Published: 2026-09-06T17:49:16.014Z

Updated: 2026-09-08T18:46:41.865Z

Reserved: 2026-08-28T08:25:31.400Z

Link: CVE-2026-82208

Vulnrichment

Updated: 2026-09-08T18:44:00.853Z

NVD

Status : Undergoing Analysis

Published: 2026-09-06T18:17:22.733

Modified: 2026-09-08T19:20:00.130

Link: CVE-2026-82208

Redhat

No data.

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-82208", "assignerOrgId": "2499f714-1537-4658-8207-48ae4bb9eae9", "state": "PUBLISHED", "assignerShortName": "curl", "dateReserved": "2026-08-28T08:25:31.400Z", "datePublished": "2026-09-06T17:49:16.014Z", "dateUpdated": "2026-09-08T18:46:41.865Z"}, "containers": {"cna": {"title": "wolfSSL CA-cache hit overrides callback", "descriptions": [{"lang": "en", "value": "With the wolfSSL backend, when CA caching is enabled and an\n`CURLOPT_SSL_CTX_FUNCTION` callback replaces the trust store, libcurl can\nsilently reinstall the cached store after the callback returns. A certificate\ntrusted by the cached store but rejected by the callback-selected store is\nthen incorrectly accepted."}], "providerMetadata": {"orgId": "2499f714-1537-4658-8207-48ae4bb9eae9", "shortName": "curl", "dateUpdated": "2026-09-06T17:49:16.014Z"}, "problemTypes": [{"descriptions": [{"lang": "en", "description": "CWE-295 Improper Certificate Validation"}]}], "affected": [{"vendor": "curl", "product": "curl", "versions": [{"version": "8.21.0", "status": "affected", "lessThanOrEqual": "8.21.0", "versionType": "semver"}, {"version": "8.20.0", "status": "affected", "lessThanOrEqual": "8.20.0", "versionType": "semver"}, {"version": "8.19.0", "status": "affected", "lessThanOrEqual": "8.19.0", "versionType": "semver"}, {"version": "8.18.0", "status": "affected", "lessThanOrEqual": "8.18.0", "versionType": "semver"}, {"version": "8.17.0", "status": "affected", "lessThanOrEqual": "8.17.0", "versionType": "semver"}, {"version": "8.16.0", "status": "affected", "lessThanOrEqual": "8.16.0", "versionType": "semver"}, {"version": "8.15.0", "status": "affected", "lessThanOrEqual": "8.15.0", "versionType": "semver"}, {"version": "8.14.1", "status": "affected", "lessThanOrEqual": "8.14.1", "versionType": "semver"}, {"version": "8.14.0", "status": "affected", "lessThanOrEqual": "8.14.0", "versionType": "semver"}, {"version": "8.13.0", "status": "affected", "lessThanOrEqual": "8.13.0", "versionType": "semver"}, {"version": "8.12.1", "status": "affected", "lessThanOrEqual": "8.12.1", "versionType": "semver"}, {"version": "8.12.0", "status": "affected", "lessThanOrEqual": "8.12.0", "versionType": "semver"}, {"version": "8.11.1", "status": "affected", "lessThanOrEqual": "8.11.1", "versionType": "semver"}, {"version": "8.11.0", "status": "affected", "lessThanOrEqual": "8.11.0", "versionType": "semver"}, {"version": "8.10.1", "status": "affected", "lessThanOrEqual": "8.10.1", "versionType": "semver"}, {"version": "8.10.0", "status": "affected", "lessThanOrEqual": "8.10.0", "versionType": "semver"}, {"version": "8.9.1", "status": "affected", "lessThanOrEqual": "8.9.1", "versionType": "semver"}], "defaultStatus": "unaffected"}], "references": [{"url": "https://curl.se/docs/CVE-2026-82208.json", "name": "json"}, {"url": "https://curl.se/docs/CVE-2026-82208.html", "name": "www"}, {"url": "https://hackerone.com/reports/3973090", "name": "issue"}], "credits": [{"lang": "en", "value": "Stanislav Fort (Aisle Research)", "type": "finder"}, {"lang": "en", "value": "Stefan Eissing", "type": "remediation developer"}]}, "adp": [{"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-295", "lang": "en", "description": "CWE-295 Improper Certificate Validation"}]}], "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-09-08T18:46:24.528833Z", "id": "CVE-2026-82208", "options": [{"Exploitation": "poc"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-08T18:46:41.865Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2026-82208", "role": "CISA Coordinator", "options": [{"Exploitation": "poc"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-08T18:46:24.528833Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-295", "description": "CWE-295 Improper Certificate Validation"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-08T18:44:00.853Z"}}], "cna": {"title": "wolfSSL CA-cache hit overrides callback", "credits": [{"lang": "en", "type": "finder", "value": "Stanislav Fort (Aisle Research)"}, {"lang": "en", "type": "remediation developer", "value": "Stefan Eissing"}], "affected": [{"vendor": "curl", "product": "curl", "versions": [{"status": "affected", "version": "8.21.0", "versionType": "semver", "lessThanOrEqual": "8.21.0"}, {"status": "affected", "version": "8.20.0", "versionType": "semver", "lessThanOrEqual": "8.20.0"}, {"status": "affected", "version": "8.19.0", "versionType": "semver", "lessThanOrEqual": "8.19.0"}, {"status": "affected", "version": "8.18.0", "versionType": "semver", "lessThanOrEqual": "8.18.0"}, {"status": "affected", "version": "8.17.0", "versionType": "semver", "lessThanOrEqual": "8.17.0"}, {"status": "affected", "version": "8.16.0", "versionType": "semver", "lessThanOrEqual": "8.16.0"}, {"status": "affected", "version": "8.15.0", "versionType": "semver", "lessThanOrEqual": "8.15.0"}, {"status": "affected", "version": "8.14.1", "versionType": "semver", "lessThanOrEqual": "8.14.1"}, {"status": "affected", "version": "8.14.0", "versionType": "semver", "lessThanOrEqual": "8.14.0"}, {"status": "affected", "version": "8.13.0", "versionType": "semver", "lessThanOrEqual": "8.13.0"}, {"status": "affected", "version": "8.12.1", "versionType": "semver", "lessThanOrEqual": "8.12.1"}, {"status": "affected", "version": "8.12.0", "versionType": "semver", "lessThanOrEqual": "8.12.0"}, {"status": "affected", "version": "8.11.1", "versionType": "semver", "lessThanOrEqual": "8.11.1"}, {"status": "affected", "version": "8.11.0", "versionType": "semver", "lessThanOrEqual": "8.11.0"}, {"status": "affected", "version": "8.10.1", "versionType": "semver", "lessThanOrEqual": "8.10.1"}, {"status": "affected", "version": "8.10.0", "versionType": "semver", "lessThanOrEqual": "8.10.0"}, {"status": "affected", "version": "8.9.1", "versionType": "semver", "lessThanOrEqual": "8.9.1"}], "defaultStatus": "unaffected"}], "references": [{"url": "https://curl.se/docs/CVE-2026-82208.json", "name": "json"}, {"url": "https://curl.se/docs/CVE-2026-82208.html", "name": "www"}, {"url": "https://hackerone.com/reports/3973090", "name": "issue"}], "descriptions": [{"lang": "en", "value": "With the wolfSSL backend, when CA caching is enabled and an\n`CURLOPT_SSL_CTX_FUNCTION` callback replaces the trust store, libcurl can\nsilently reinstall the cached store after the callback returns. A certificate\ntrusted by the cached store but rejected by the callback-selected store is\nthen incorrectly accepted."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "CWE-295 Improper Certificate Validation"}]}], "providerMetadata": {"orgId": "2499f714-1537-4658-8207-48ae4bb9eae9", "shortName": "curl", "dateUpdated": "2026-09-06T17:49:16.014Z"}}}, "cveMetadata": {"cveId": "CVE-2026-82208", "state": "PUBLISHED", "dateUpdated": "2026-09-08T18:46:41.865Z", "dateReserved": "2026-08-28T08:25:31.400Z", "assignerOrgId": "2499f714-1537-4658-8207-48ae4bb9eae9", "datePublished": "2026-09-06T17:49:16.014Z", "assignerShortName": "curl"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "curl", "vendor": "curl", "versions": [{"lessThanOrEqual": "8.21.0", "status": "affected", "version": "8.21.0", "versionType": "semver"}, {"lessThanOrEqual": "8.20.0", "status": "affected", "version": "8.20.0", "versionType": "semver"}, {"lessThanOrEqual": "8.19.0", "status": "affected", "version": "8.19.0", "versionType": "semver"}, {"lessThanOrEqual": "8.18.0", "status": "affected", "version": "8.18.0", "versionType": "semver"}, {"lessThanOrEqual": "8.17.0", "status": "affected", "version": "8.17.0", "versionType": "semver"}, {"lessThanOrEqual": "8.16.0", "status": "affected", "version": "8.16.0", "versionType": "semver"}, {"lessThanOrEqual": "8.15.0", "status": "affected", "version": "8.15.0", "versionType": "semver"}, {"lessThanOrEqual": "8.14.1", "status": "affected", "version": "8.14.1", "versionType": "semver"}, {"lessThanOrEqual": "8.14.0", "status": "affected", "version": "8.14.0", "versionType": "semver"}, {"lessThanOrEqual": "8.13.0", "status": "affected", "version": "8.13.0", "versionType": "semver"}, {"lessThanOrEqual": "8.12.1", "status": "affected", "version": "8.12.1", "versionType": "semver"}, {"lessThanOrEqual": "8.12.0", "status": "affected", "version": "8.12.0", "versionType": "semver"}, {"lessThanOrEqual": "8.11.1", "status": "affected", "version": "8.11.1", "versionType": "semver"}, {"lessThanOrEqual": "8.11.0", "status": "affected", "version": "8.11.0", "versionType": "semver"}, {"lessThanOrEqual": "8.10.1", "status": "affected", "version": "8.10.1", "versionType": "semver"}, {"lessThanOrEqual": "8.10.0", "status": "affected", "version": "8.10.0", "versionType": "semver"}, {"lessThanOrEqual": "8.9.1", "status": "affected", "version": "8.9.1", "versionType": "semver"}]}], "source": "2499f714-1537-4658-8207-48ae4bb9eae9"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "With the wolfSSL backend, when CA caching is enabled and an\n`CURLOPT_SSL_CTX_FUNCTION` callback replaces the trust store, libcurl can\nsilently reinstall the cached store after the callback returns. A certificate\ntrusted by the cached store but rejected by the callback-selected store is\nthen incorrectly accepted."}], "id": "CVE-2026-82208", "lastModified": "2026-09-08T19:20:00.130", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-82208", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-08T18:46:24.528833Z", "version": "2.0.3"}}]}, "published": "2026-09-06T18:17:22.733", "references": [{"source": "2499f714-1537-4658-8207-48ae4bb9eae9", "url": "https://curl.se/docs/CVE-2026-82208.html"}, {"source": "2499f714-1537-4658-8207-48ae4bb9eae9", "url": "https://curl.se/docs/CVE-2026-82208.json"}, {"source": "2499f714-1537-4658-8207-48ae4bb9eae9", "url": "https://hackerone.com/reports/3973090"}], "sourceIdentifier": "2499f714-1537-4658-8207-48ae4bb9eae9", "vulnStatus": "Undergoing Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-295"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}