FKIE_CVE-2026-11856
Vulnerability from fkie_nvd - Published: 2026-07-03 07:16 - Updated: 2026-09-15 07:16
Severity
Summary
Successfully using libcurl to do a transfer to a specific HTTP origin
(`hostA`) with **Digest** authentication and then changing the origin to a
different one (`hostB`) for a second transfer, reusing the same handle, makes
libcurl wrongly pass on the `Authorization:` header field meant for `hostA`,
to `hostB`.
References
| URL | Tags | ||
|---|---|---|---|
| 2499f714-1537-4658-8207-48ae4bb9eae9 | https://curl.se/docs/CVE-2026-11856.html | Patch, Vendor Advisory | |
| 2499f714-1537-4658-8207-48ae4bb9eae9 | https://curl.se/docs/CVE-2026-11856.json | Vendor Advisory | |
| 2499f714-1537-4658-8207-48ae4bb9eae9 | https://hackerone.com/reports/3793260 | Exploit, Issue Tracking, Third Party Advisory | |
| 134c704f-9b21-4f2e-91b3-4a467353bcc0 | https://hackerone.com/reports/3793260 | Exploit, Issue Tracking, Third Party Advisory |
{
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "curl",
"vendor": "curl",
"versions": [
{
"lessThan": "8.14.2",
"status": "affected",
"version": "7.10.6",
"versionType": "semver"
},
{
"lessThan": "8.16.1",
"status": "affected",
"version": "8.15.0",
"versionType": "semver"
},
{
"lessThan": "8.20.1",
"status": "affected",
"version": "8.17.0",
"versionType": "semver"
}
]
},
{
"defaultStatus": "unaffected",
"product": "curl",
"repo": "https://github.com/curl/curl.git",
"vendor": "curl",
"versions": [
{
"lessThan": "5c6b4880357ab3e72967c1c45cae0f96ffabc535",
"status": "affected",
"version": "334d78cd18a7310144383929bdcef34ffbf6159b",
"versionType": "git"
}
]
},
{
"defaultStatus": "unaffected",
"product": "curl",
"vendor": "curl",
"versions": [
{
"status": "affected",
"version": "8.20.0"
},
{
"status": "affected",
"version": "8.19.0"
},
{
"status": "affected",
"version": "8.18.0"
},
{
"status": "affected",
"version": "8.17.0"
},
{
"status": "affected",
"version": "8.16.0"
},
{
"status": "affected",
"version": "8.15.0"
},
{
"status": "affected",
"version": "8.14.1"
},
{
"status": "affected",
"version": "8.14.0"
},
{
"status": "affected",
"version": "8.13.0"
},
{
"status": "affected",
"version": "8.12.1"
},
{
"status": "affected",
"version": "8.12.0"
},
{
"status": "affected",
"version": "8.11.1"
},
{
"status": "affected",
"version": "8.11.0"
},
{
"status": "affected",
"version": "8.10.1"
},
{
"status": "affected",
"version": "8.10.0"
},
{
"status": "affected",
"version": "8.9.1"
},
{
"status": "affected",
"version": "8.9.0"
},
{
"status": "affected",
"version": "8.8.0"
},
{
"status": "affected",
"version": "8.7.1"
},
{
"status": "affected",
"version": "8.7.0"
},
{
"status": "affected",
"version": "8.6.0"
},
{
"status": "affected",
"version": "8.5.0"
},
{
"status": "affected",
"version": "8.4.0"
},
{
"status": "affected",
"version": "8.3.0"
},
{
"status": "affected",
"version": "8.2.1"
},
{
"status": "affected",
"version": "8.2.0"
},
{
"status": "affected",
"version": "8.1.2"
},
{
"status": "affected",
"version": "8.1.1"
},
{
"status": "affected",
"version": "8.1.0"
},
{
"status": "affected",
"version": "8.0.1"
},
{
"status": "affected",
"version": "8.0.0"
},
{
"status": "affected",
"version": "7.88.1"
},
{
"status": "affected",
"version": "7.88.0"
},
{
"status": "affected",
"version": "7.87.0"
},
{
"status": "affected",
"version": "7.86.0"
},
{
"status": "affected",
"version": "7.85.0"
},
{
"status": "affected",
"version": "7.84.0"
},
{
"status": "affected",
"version": "7.83.1"
},
{
"status": "affected",
"version": "7.83.0"
},
{
"status": "affected",
"version": "7.82.0"
},
{
"status": "affected",
"version": "7.81.0"
},
{
"status": "affected",
"version": "7.80.0"
},
{
"status": "affected",
"version": "7.79.1"
},
{
"status": "affected",
"version": "7.79.0"
},
{
"status": "affected",
"version": "7.78.0"
},
{
"status": "affected",
"version": "7.77.0"
},
{
"status": "affected",
"version": "7.76.1"
},
{
"status": "affected",
"version": "7.76.0"
},
{
"status": "affected",
"version": "7.75.0"
},
{
"status": "affected",
"version": "7.74.0"
},
{
"status": "affected",
"version": "7.73.0"
},
{
"status": "affected",
"version": "7.72.0"
},
{
"status": "affected",
"version": "7.71.1"
},
{
"status": "affected",
"version": "7.71.0"
},
{
"status": "affected",
"version": "7.70.0"
},
{
"status": "affected",
"version": "7.69.1"
},
{
"status": "affected",
"version": "7.69.0"
},
{
"status": "affected",
"version": "7.68.0"
},
{
"status": "affected",
"version": "7.67.0"
},
{
"status": "affected",
"version": "7.66.0"
},
{
"status": "affected",
"version": "7.65.3"
},
{
"status": "affected",
"version": "7.65.2"
},
{
"status": "affected",
"version": "7.65.1"
},
{
"status": "affected",
"version": "7.65.0"
},
{
"status": "affected",
"version": "7.64.1"
},
{
"status": "affected",
"version": "7.64.0"
},
{
"status": "affected",
"version": "7.63.0"
},
{
"status": "affected",
"version": "7.62.0"
},
{
"status": "affected",
"version": "7.61.1"
},
{
"status": "affected",
"version": "7.61.0"
},
{
"status": "affected",
"version": "7.60.0"
},
{
"status": "affected",
"version": "7.59.0"
},
{
"status": "affected",
"version": "7.58.0"
},
{
"status": "affected",
"version": "7.57.0"
},
{
"status": "affected",
"version": "7.56.1"
},
{
"status": "affected",
"version": "7.56.0"
},
{
"status": "affected",
"version": "7.55.1"
},
{
"status": "affected",
"version": "7.55.0"
},
{
"status": "affected",
"version": "7.54.1"
},
{
"status": "affected",
"version": "7.54.0"
},
{
"status": "affected",
"version": "7.53.1"
},
{
"status": "affected",
"version": "7.53.0"
},
{
"status": "affected",
"version": "7.52.1"
},
{
"status": "affected",
"version": "7.52.0"
},
{
"status": "affected",
"version": "7.51.0"
},
{
"status": "affected",
"version": "7.50.3"
},
{
"status": "affected",
"version": "7.50.2"
},
{
"status": "affected",
"version": "7.50.1"
},
{
"status": "affected",
"version": "7.50.0"
},
{
"status": "affected",
"version": "7.49.1"
},
{
"status": "affected",
"version": "7.49.0"
},
{
"status": "affected",
"version": "7.48.0"
},
{
"status": "affected",
"version": "7.47.1"
},
{
"status": "affected",
"version": "7.47.0"
},
{
"status": "affected",
"version": "7.46.0"
},
{
"status": "affected",
"version": "7.45.0"
},
{
"status": "affected",
"version": "7.44.0"
},
{
"status": "affected",
"version": "7.43.0"
},
{
"status": "affected",
"version": "7.42.1"
},
{
"status": "affected",
"version": "7.42.0"
},
{
"status": "affected",
"version": "7.41.0"
},
{
"status": "affected",
"version": "7.40.0"
},
{
"status": "affected",
"version": "7.39.0"
},
{
"status": "affected",
"version": "7.38.0"
},
{
"status": "affected",
"version": "7.37.1"
},
{
"status": "affected",
"version": "7.37.0"
},
{
"status": "affected",
"version": "7.36.0"
},
{
"status": "affected",
"version": "7.35.0"
},
{
"status": "affected",
"version": "7.34.0"
},
{
"status": "affected",
"version": "7.33.0"
},
{
"status": "affected",
"version": "7.32.0"
},
{
"status": "affected",
"version": "7.31.0"
},
{
"status": "affected",
"version": "7.30.0"
},
{
"status": "affected",
"version": "7.29.0"
},
{
"status": "affected",
"version": "7.28.1"
},
{
"status": "affected",
"version": "7.28.0"
},
{
"status": "affected",
"version": "7.27.0"
},
{
"status": "affected",
"version": "7.26.0"
},
{
"status": "affected",
"version": "7.25.0"
},
{
"status": "affected",
"version": "7.24.0"
},
{
"status": "affected",
"version": "7.23.1"
},
{
"status": "affected",
"version": "7.23.0"
},
{
"status": "affected",
"version": "7.22.0"
},
{
"status": "affected",
"version": "7.21.7"
},
{
"status": "affected",
"version": "7.21.6"
},
{
"status": "affected",
"version": "7.21.5"
},
{
"status": "affected",
"version": "7.21.4"
},
{
"status": "affected",
"version": "7.21.3"
},
{
"status": "affected",
"version": "7.21.2"
},
{
"status": "affected",
"version": "7.21.1"
},
{
"status": "affected",
"version": "7.21.0"
},
{
"status": "affected",
"version": "7.20.1"
},
{
"status": "affected",
"version": "7.20.0"
},
{
"status": "affected",
"version": "7.19.7"
},
{
"status": "affected",
"version": "7.19.6"
},
{
"status": "affected",
"version": "7.19.5"
},
{
"status": "affected",
"version": "7.19.4"
},
{
"status": "affected",
"version": "7.19.3"
},
{
"status": "affected",
"version": "7.19.2"
},
{
"status": "affected",
"version": "7.19.1"
},
{
"status": "affected",
"version": "7.19.0"
},
{
"status": "affected",
"version": "7.18.2"
},
{
"status": "affected",
"version": "7.18.1"
},
{
"status": "affected",
"version": "7.18.0"
},
{
"status": "affected",
"version": "7.17.1"
},
{
"status": "affected",
"version": "7.17.0"
},
{
"status": "affected",
"version": "7.16.4"
},
{
"status": "affected",
"version": "7.16.3"
},
{
"status": "affected",
"version": "7.16.2"
},
{
"status": "affected",
"version": "7.16.1"
},
{
"status": "affected",
"version": "7.16.0"
},
{
"status": "affected",
"version": "7.15.5"
},
{
"status": "affected",
"version": "7.15.4"
},
{
"status": "affected",
"version": "7.15.3"
},
{
"status": "affected",
"version": "7.15.2"
},
{
"status": "affected",
"version": "7.15.1"
},
{
"status": "affected",
"version": "7.15.0"
},
{
"status": "affected",
"version": "7.14.1"
},
{
"status": "affected",
"version": "7.14.0"
},
{
"status": "affected",
"version": "7.13.2"
},
{
"status": "affected",
"version": "7.13.1"
},
{
"status": "affected",
"version": "7.13.0"
},
{
"status": "affected",
"version": "7.12.3"
},
{
"status": "affected",
"version": "7.12.2"
},
{
"status": "affected",
"version": "7.12.1"
},
{
"status": "affected",
"version": "7.12.0"
},
{
"status": "affected",
"version": "7.11.2"
},
{
"status": "affected",
"version": "7.11.1"
},
{
"status": "affected",
"version": "7.11.0"
},
{
"status": "affected",
"version": "7.10.8"
},
{
"status": "affected",
"version": "7.10.7"
},
{
"status": "affected",
"version": "7.10.6"
}
]
}
],
"source": "2499f714-1537-4658-8207-48ae4bb9eae9"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*",
"matchCriteriaId": "9E12CA71-3AD8-44FB-9A48-E1CD9551EDE8",
"versionEndExcluding": "8.21.0",
"versionStartIncluding": "7.10.6",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Successfully using libcurl to do a transfer to a specific HTTP origin\n(`hostA`) with **Digest** authentication and then changing the origin to a\ndifferent one (`hostB`) for a second transfer, reusing the same handle, makes\nlibcurl wrongly pass on the `Authorization:` header field meant for `hostA`,\nto `hostB`."
}
],
"id": "CVE-2026-11856",
"lastModified": "2026-09-15T07:16:25.870",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 9.8,
"baseSeverity": "CRITICAL",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 3.9,
"impactScore": 5.9,
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-11856",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-07-06T18:22:46.260282Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-07-03T07:16:23.973",
"references": [
{
"source": "2499f714-1537-4658-8207-48ae4bb9eae9",
"tags": [
"Patch",
"Vendor Advisory"
],
"url": "https://curl.se/docs/CVE-2026-11856.html"
},
{
"source": "2499f714-1537-4658-8207-48ae4bb9eae9",
"tags": [
"Vendor Advisory"
],
"url": "https://curl.se/docs/CVE-2026-11856.json"
},
{
"source": "2499f714-1537-4658-8207-48ae4bb9eae9",
"tags": [
"Exploit",
"Issue Tracking",
"Third Party Advisory"
],
"url": "https://hackerone.com/reports/3793260"
},
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"tags": [
"Exploit",
"Issue Tracking",
"Third Party Advisory"
],
"url": "https://hackerone.com/reports/3793260"
}
],
"sourceIdentifier": "2499f714-1537-4658-8207-48ae4bb9eae9",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-294"
}
],
"source": "2499f714-1537-4658-8207-48ae4bb9eae9",
"type": "Secondary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-294"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…