CURL-CVE-2023-28321

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Source
https://curl.se/docs/CVE-2023-28321.html
Import Source
https://curl.se/docs/CURL-CVE-2023-28321.json
JSON Data
https://api.osv.dev/v1/vulns/CURL-CVE-2023-28321
Aliases
Published
2023-05-17T08:00:00Z
Modified
2026-05-27T02:29:16.096613Z
Summary
IDN wildcard match
Details

curl supports matching of wildcard patterns when listed as "Subject Alternative Name" in TLS server certificates. curl can be built to use its own name matching function for TLS rather than one provided by a TLS library. This private wildcard matching function would match IDN (International Domain Name) hosts incorrectly and could as a result accept patterns that otherwise should mismatch.

IDN hostnames are converted to puny code before used for certificate checks. Puny coded names always start with xn-- and should not be allowed to pattern match, but the wildcard check in curl could still check for x*, which would match even though the IDN name most likely contained nothing even resembling an x.

Database specific 
{
    "award": {
        "currency": "USD",
        "amount": "480"
    },
    "www": "https://curl.se/docs/CVE-2023-28321.html",
    "issue": "https://hackerone.com/reports/1950627",
    "package": "curl",
    "severity": "Low",
    "CWE": {
        "desc": "Improper Certificate Validation",
        "id": "CWE-295"
    },
    "affects": "both",
    "last_affected": "8.0.1",
    "URL": "https://curl.se/docs/CVE-2023-28321.json"
}
References
Credits
    • Hiroki Kurosawa - FINDER
    • Daniel Stenberg - REMEDIATION_DEVELOPER

Affected packages

Git / github.com/curl/curl.git

Affected ranges

Type
SEMVER
Events
Introduced
7.12.0
Fixed
8.1.0
Type
GIT
Repo
https://github.com/curl/curl.git
Events
Introduced
9631fa740708b1890197fad01e25b34b7e8eb80e
Fixed
199f2d440d8659b42670c1b796220792b01a97bf

Affected versions

7.*
7.12.0
7.12.1
7.12.2
7.12.3
7.13.0
7.13.1
7.13.2
7.14.0
7.14.1
7.15.0
7.15.1
7.15.2
7.15.3
7.15.4
7.15.5
7.16.0
7.16.1
7.16.2
7.16.3
7.16.4
7.17.0
7.17.1
7.18.0
7.18.1
7.18.2
7.19.0
7.19.1
7.19.2
7.19.3
7.19.4
7.19.5
7.19.6
7.19.7
7.20.0
7.20.1
7.21.0
7.21.1
7.21.2
7.21.3
7.21.4
7.21.5
7.21.6
7.21.7
7.22.0
7.23.0
7.23.1
7.24.0
7.25.0
7.26.0
7.27.0
7.28.0
7.28.1
7.29.0
7.30.0
7.31.0
7.32.0
7.33.0
7.34.0
7.35.0
7.36.0
7.37.0
7.37.1
7.38.0
7.39.0
7.40.0
7.41.0
7.42.0
7.42.1
7.43.0
7.44.0
7.45.0
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
Other
before_ftp_statemachine
curl-7_12_0
curl-7_12_1
curl-7_12_2
curl-7_12_3
curl-7_13_0
curl-7_13_1
curl-7_13_2
curl-7_14_0
curl-7_14_1
curl-7_15_0
curl-7_15_1
curl-7_15_2
curl-7_15_3
curl-7_15_4
curl-7_15_5
curl-7_15_6-prepipeline
curl-7_16_0
curl-7_16_1
curl-7_16_2
curl-7_16_3
curl-7_16_4
curl-7_17_0
curl-7_17_0-preldapfix
curl-7_17_1
curl-7_18_0
curl-7_18_1
curl-7_18_2
curl-7_19_0
curl-7_19_1
curl-7_19_2
curl-7_19_3
curl-7_19_4
curl-7_19_5
curl-7_19_6
curl-7_19_7
curl-7_20_0
curl-7_20_1
curl-7_21_0
curl-7_21_1
curl-7_21_2
curl-7_21_3
curl-7_21_4
curl-7_21_5
curl-7_21_6
curl-7_21_7
curl-7_22_0
curl-7_23_0
curl-7_23_1
curl-7_24_0
curl-7_25_0
curl-7_26_0
curl-7_27_0
curl-7_28_0
curl-7_28_1
curl-7_29_0
curl-7_30_0
curl-7_31_0
curl-7_32_0
curl-7_33_0
curl-7_34_0
curl-7_35_0
curl-7_36_0
curl-7_37_0
curl-7_37_1
curl-7_38_0
curl-7_39_0
curl-7_40_0
curl-7_41_0
curl-7_42_0
curl-7_42_1
curl-7_43_0
curl-7_44_0
curl-7_45_0
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
tiny-curl-7_72_0

Database specific

vanir_signatures_modified 
"2026-05-27T02:29:16Z"
source 
"https://curl.se/docs/CURL-CVE-2023-28321.json"
vanir_signatures 
[
    {
        "digest": {
            "threshold": 0.9,
            "line_hashes": [
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                "176450998410173016986681428109077048181",
                "96678665506437293532820654154268634943",
                "244917099847138194886333478503103950628",
                "290144097704787677007989522158933197135",
                "202219654548396747986612148741026476277",
                "106261824755708513465249537150556334520",
                "292781301319785374301973628429098761201",
                "182884367375154701311730416210809079942",
                "184850878051911525171318602240408755679",
                "70872935137333767821928064781034318777",
                "3218818267648832516109818594963966423",
                "259002975747539925722061061352013899141",
                "119503835549450692804905006096445230805",
                "237906647485658698509995646830117046063",
                "64558883178164103185559295669389519803",
                "43332104367442266067511898126447375423",
                "220485707103904345636038975245330103165",
                "32938390744849936639465126910748883463",
                "84499700343107277191071546829722903595",
                "174494594992661535818975793588245730124",
                "18750924031455055675408890960159457343",
                "70030276913893605866929172575700190452",
                "297133321672383619089091827377126209520",
                "13527663011686220506134752011245117688",
                "209178442964219701653566614313755601921",
                "293711842609800845236651907376106789971",
                "14533965421150270866906735132835572603",
                "267120981018669293215323945650870185363",
                "196391514796541536002487959221554985156",
                "227015790769795376859760859938160102021",
                "316663134325251650730551586338244840937",
                "117758670353837784665922420908474672441",
                "224605571622261455075235519821174555378",
                "20187487501335244557122662571306469028",
                "181801461867350828320927042053029239737",
                "236451809119585836700513312873152680197",
                "29513611501008744280691819268018259285",
                "145529806693255241543554255050574402265",
                "79088044851467495900347924277634283669",
                "287269455687870498246737122626929890878",
                "187152424406849004443345873939226419529",
                "128390619606535394460267015126923126753",
                "215332077111943297502664971507561531214",
                "315765897946706647711754345569895997735",
                "323163036058898178658777904662209436316",
                "106341659433086469923964117145680371865",
                "176671770801296029345261879167953368048",
                "149904613802364529128234921182639223146"
            ]
        },
        "target": {
            "file": "tests/unit/unit1397.c"
        },
        "signature_type": "Line",
        "signature_version": "v1",
        "deprecated": false,
        "id": "CURL-CVE-2023-28321-22907c43",
        "source": "https://github.com/curl/curl.git/commit/199f2d440d8659b42670c1b796220792b01a97bf"
    },
    {
        "digest": {
            "length": 997.0,
            "function_hash": "17045556477640101631476317217175158095"
        },
        "target": {
            "file": "lib/vtls/hostcheck.c",
            "function": "hostmatch"
        },
        "signature_type": "Function",
        "signature_version": "v1",
        "deprecated": false,
        "id": "CURL-CVE-2023-28321-8ed8cea1",
        "source": "https://github.com/curl/curl.git/commit/199f2d440d8659b42670c1b796220792b01a97bf"
    },
    {
        "digest": {
            "threshold": 0.9,
            "line_hashes": [
                "202480558793927032443896057348026301333",
                "273735333512926019706092675697435160329",
                "34575677330080548715188934758914392689",
                "161833313914807409501102786217462292561",
                "238242421435260085330126269803896816368",
                "273956007976646414983790013364135847729",
                "230972920637210048503660159829816561017",
                "259847689724216513183948545756757181743",
                "150274663693921415380239290079727876828",
                "65363549928569964557700014265241454880",
                "150200142490441987707881659854018231823",
                "173788023322784971571172798032121242752",
                "132679290044646887355311276072621944872",
                "25619242862421188163039260771649062645",
                "144281374625316198945495567413221501820",
                "99020688279056881216991553987430980562",
                "14968558949702634202354716346518045466",
                "255582497584182576484126104750823177411",
                "85790513418043162373358032904296192892",
                "99212506937494681883937530713434009897",
                "163907589584131067719163211430603514158",
                "178650692711719712051589754764022254573",
                "4542696306003919669504041750104887642",
                "304976047544308717997234158838631226087",
                "13064021874927037628782388118336597786",
                "16708449399330014789651151293084031438",
                "695481965351811090486431716371694364",
                "329086040007228194495918905846678174541",
                "219827008063691352413220017409881238791",
                "178318043334528255561670293008793434335",
                "92308745483557585579030948033692739499",
                "308741393931263726980266449695143080759",
                "91327533059102227972066396834652786653",
                "76123061512330118630165763077009240403",
                "45687453402880191195503626419558990401",
                "211643802336353119040804615758864243236",
                "283446933028853935968841514268993513422",
                "235139287545283987764083845890182220162",
                "176748493745458278603251314540948026316",
                "162666952330111013622416839259305747227"
            ]
        },
        "target": {
            "file": "lib/vtls/hostcheck.c"
        },
        "signature_type": "Line",
        "signature_version": "v1",
        "deprecated": false,
        "id": "CURL-CVE-2023-28321-c9a94bbc",
        "source": "https://github.com/curl/curl.git/commit/199f2d440d8659b42670c1b796220792b01a97bf"
    }
]