CURL-CVE-2026-80255

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Source
https://curl.se/docs/CVE-2026-80255.html
Import Source
https://curl.se/docs/CURL-CVE-2026-80255.json
JSON Data
https://api.osv.dev/v1/vulns/CURL-CVE-2026-80255
Aliases
  • CVE-2026-80255
Published
2026-09-02T08:00:00Z
Modified
2026-09-03T02:01:08.203846Z
Summary
secure cookie attribute bypass with tab
Details

A Set-Cookie: header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the Secure attribute causes curl to store the cookie without its Secure flag. The cookie might then wrongfully be sent over plaintext HTTP on subsequent requests to the same host.

Database specific 
{
    "URL": "https://curl.se/docs/CVE-2026-80255.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-2026-80255.html",
    "severity": "Low",
    "issue": "https://hackerone.com/reports/3972395"
}
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
8.13.0
Fixed
8.22.0
Type
GIT
Repo
https://github.com/curl/curl.git
Events
Introduced
1aea05a6c2699e80c75936d58569851555acd603
Fixed
4f6aa41a0145e930e766775dbe860883d350aa0a

Affected versions

8.*
8.13.0
8.14.0
8.14.1
8.15.0
8.16.0
8.17.0
8.18.0
8.19.0
8.20.0
8.21.0
Other
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_20_0
curl-8_21_0
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

Database specific

vanir_signatures 
[
    {
        "signature_type": "Function",
        "deprecated": false,
        "digest": {
            "length": 1807.0,
            "function_hash": "156248508838678620174316832758863728670"
        },
        "id": "CURL-CVE-2026-80255-1976306a",
        "target": {
            "function": "parse_cookie_header",
            "file": "lib/cookie.c"
        },
        "source": "https://github.com/curl/curl.git/commit/4f6aa41a0145e930e766775dbe860883d350aa0a",
        "signature_version": "v1"
    },
    {
        "signature_type": "Line",
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "205816004684899671603710379302867268706",
                "18514482557387433468133516516178791980",
                "274291864640093038674042589109486318957",
                "147342966625047719758808367123869032769"
            ],
            "threshold": 0.9
        },
        "id": "CURL-CVE-2026-80255-d501f15b",
        "target": {
            "file": "lib/cookie.c"
        },
        "source": "https://github.com/curl/curl.git/commit/4f6aa41a0145e930e766775dbe860883d350aa0a",
        "signature_version": "v1"
    }
]
source 
"https://curl.se/docs/CURL-CVE-2026-80255.json"
vanir_signatures_modified 
"2026-09-03T02:01:08Z"