CURL-CVE-2026-82209

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Source
https://curl.se/docs/CVE-2026-82209.html
Import Source
https://curl.se/docs/CURL-CVE-2026-82209.json
JSON Data
https://api.osv.dev/v1/vulns/CURL-CVE-2026-82209
Aliases
  • CVE-2026-82209
Published
2026-09-02T08:00:00Z
Modified
2026-09-02T08:04:19.510649Z
Summary
domain-scoped PSL domain cookie
Details

When libpsl support is enabled, libcurl fails to enforce the Public Suffix List boundary check when processing a Set-Cookie header where the Domain attribute explicitly matches an origin host that is itself a public suffix (e.g., Domain=co.uk set by co.uk).

Instead of coercing it into a strict host-only cookie, libcurl saves the cookie with wildcard domain scope (.co.uk). Consequently, the cookie is inappropriately included in subsequent outbound requests or HTTP redirects to arbitrary sibling subdomains under the same public suffix (e.g., attacker.co.uk).

Database specific 
{
    "URL": "https://curl.se/docs/CVE-2026-82209.json",
    "CWE": {
        "desc": "Information Exposure Through Sent Data",
        "id": "CWE-201"
    },
    "package": "curl",
    "affects": "both",
    "last_affected": "8.21.0",
    "www": "https://curl.se/docs/CVE-2026-82209.html",
    "severity": "Low",
    "issue": "https://hackerone.com/reports/3972385"
}
References
Credits
    • Stanislav Fort (Aisle Research) - FINDER
    • Daniel Stenberg - REMEDIATION_DEVELOPER

Affected packages

Git / github.com/curl/curl.git

Affected ranges

Type
SEMVER
Events
Introduced
7.46.0
Fixed
8.22.0
Type
GIT
Repo
https://github.com/curl/curl.git
Events
Introduced
e77b5b7453c1e8ccd7ec0816890d98e2f392e465
Fixed
95c1e8915dce64606bd753fd47fc0bd236e31cd6

Affected versions

7.*
7.46.0
7.47.0
7.47.1
7.48.0
7.49.0
7.49.1
7.50.0
7.50.1
7.50.2
7.50.3
7.51.0
7.52.0
7.52.1
7.53.0
7.53.1
7.54.0
7.54.1
7.55.0
7.55.1
7.56.0
7.56.1
7.57.0
7.58.0
7.59.0
7.60.0
7.61.0
7.61.1
7.62.0
7.63.0
7.64.0
7.64.1
7.65.0
7.65.1
7.65.2
7.65.3
7.66.0
7.67.0
7.68.0
7.69.0
7.69.1
7.70.0
7.71.0
7.71.1
7.72.0
7.73.0
7.74.0
7.75.0
7.76.0
7.76.1
7.77.0
7.78.0
7.79.0
7.79.1
7.80.0
7.81.0
7.82.0
7.83.0
7.83.1
7.84.0
7.85.0
7.86.0
7.87.0
7.88.0
7.88.1
8.*
8.0.0
8.0.1
8.1.0
8.1.1
8.1.2
8.10.0
8.10.1
8.11.0
8.11.1
8.12.0
8.12.1
8.13.0
8.14.0
8.14.1
8.15.0
8.16.0
8.17.0
8.18.0
8.19.0
8.2.0
8.2.1
8.20.0
8.21.0
8.3.0
8.4.0
8.5.0
8.6.0
8.7.0
8.7.1
8.8.0
8.9.0
8.9.1
Other
curl-7_46_0
curl-7_47_0
curl-7_47_1
curl-7_48_0
curl-7_49_0
curl-7_49_1
curl-7_50_0
curl-7_50_1
curl-7_50_2
curl-7_50_3
curl-7_51_0
curl-7_52_0
curl-7_52_1
curl-7_53_0
curl-7_53_1
curl-7_54_0
curl-7_54_1
curl-7_55_0
curl-7_55_1
curl-7_56_0
curl-7_56_1
curl-7_57_0
curl-7_58_0
curl-7_59_0
curl-7_60_0
curl-7_61_0
curl-7_61_1
curl-7_62_0
curl-7_63_0
curl-7_64_0
curl-7_64_1
curl-7_65_0
curl-7_65_1
curl-7_65_2
curl-7_65_3
curl-7_66_0
curl-7_67_0
curl-7_68_0
curl-7_69_0
curl-7_69_1
curl-7_70_0
curl-7_71_0
curl-7_71_1
curl-7_72_0
curl-7_73_0
curl-7_74_0
curl-7_75_0
curl-7_76_0
curl-7_76_1
curl-7_77_0
curl-7_78_0
curl-7_79_0
curl-7_79_1
curl-7_80_0
curl-7_81_0
curl-7_82_0
curl-7_83_0
curl-7_83_1
curl-7_84_0
curl-7_85_0
curl-7_86_0
curl-7_87_0
curl-7_88_0
curl-7_88_1
curl-8_0_0
curl-8_0_1
curl-8_10_0
curl-8_10_1
curl-8_11_0
curl-8_11_1
curl-8_12_0
curl-8_12_1
curl-8_13_0
curl-8_14_0
curl-8_14_1
curl-8_15_0
curl-8_16_0
curl-8_17_0
curl-8_18_0
curl-8_19_0
curl-8_1_0
curl-8_1_1
curl-8_1_2
curl-8_20_0
curl-8_21_0
curl-8_2_0
curl-8_2_1
curl-8_3_0
curl-8_4_0
curl-8_5_0
curl-8_6_0
curl-8_7_0
curl-8_7_1
curl-8_8_0
curl-8_9_0
curl-8_9_1
rc-8_18_0-1
rc-8_18_0-2
rc-8_18_0-3
rc-8_19_0-1
rc-8_19_0-2
rc-8_19_0-3
rc-8_20_0-1
rc-8_20_0-2
rc-8_20_0-3
rc-8_21_0-1
rc-8_21_0-2
rc-8_21_0-3
rc-8_22_0-1
rc-8_22_0-2
rc-8_22_0-3
tiny-curl-7_72_0
tiny-curl-8_4_0

Database specific

vanir_signatures 
[
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
            "length": 1541.0,
            "function_hash": "213908973564268594638752847231949979873"
        },
        "id": "CURL-CVE-2026-82209-2d294af4",
        "target": {
            "function": "is_public_suffix",
            "file": "lib/cookie.c"
        },
        "source": "https://github.com/curl/curl.git/commit/95c1e8915dce64606bd753fd47fc0bd236e31cd6",
        "signature_version": "v1"
    },
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
            "length": 1968.0,
            "function_hash": "222278781498688503787787149637841757802"
        },
        "id": "CURL-CVE-2026-82209-3e6d2661",
        "target": {
            "function": "Curl_cookie_add",
            "file": "lib/cookie.c"
        },
        "source": "https://github.com/curl/curl.git/commit/95c1e8915dce64606bd753fd47fc0bd236e31cd6",
        "signature_version": "v1"
    },
    {
        "signature_type": "Line",
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "21731868551911990400354518369227389333",
                "311339764407599575675744290038700683018",
                "67409538252246842468129996238415507633",
                "224238131650987331527718603641182882494",
                "51712989053120701785138910181342785258",
                "62922986269795145090752633040670570483",
                "92544284258673586415963021062531968348",
                "14590852356148094742011252700767634914",
                "240366736704082154951189601671281888744",
                "102088696126812935081930637958153298509",
                "3097192871563462358128540996551017003",
                "292141583597009942329457207525873703953",
                "145216581391913082276329618955851914563",
                "116388533793503780493851995865121599403",
                "53608696260299754480294834383817733622",
                "276767620444654246698632291886791423708"
            ],
            "threshold": 0.9
        },
        "id": "CURL-CVE-2026-82209-9c5731a5",
        "target": {
            "file": "lib/cookie.c"
        },
        "source": "https://github.com/curl/curl.git/commit/95c1e8915dce64606bd753fd47fc0bd236e31cd6",
        "signature_version": "v1"
    }
]
source 
"https://curl.se/docs/CURL-CVE-2026-82209.json"
vanir_signatures_modified 
"2026-09-02T08:04:19Z"