Medium
Security advisory
chmextract.c in the chmextract sample program, as distributed with libmspack before 0.8alpha, does not protect against absolute/relative pathnames in CHM files, leading to Directory Traversal. NOTE: the vendor disputes that this is a libmspack vulnerability, because chmextract.c was only intended as a source-code example, not a supported application
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2018-18586
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:12 UTC · Revision 1
Source evidence
chmextract.c in the chmextract sample program, as distributed with libmspack before 0.8alpha, does not protect against absolute/relative pathnames in CHM files, leading to Directory Traversal. NOTE: the vendor disputes that this is a libmspack vulnerability, because chmextract.c was only intended as a source-code example, not a supported application
osv:CVE-2018-18586
Complete source record
{
"id": "24d242bc1593b23553e3e30bf9bcf17a32007c0968a5bb282fe4e02b950b63b2",
"url": "https://osv.dev/vulnerability/CVE-2018-18586",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2018-18586",
"summary": "chmextract.c in the chmextract sample program, as distributed with libmspack before 0.8alpha, does not protect against absolute/relative pathnames in CHM files, leading to Directory Traversal. NOTE: the vendor disputes that this is a libmspack vulnerability, because chmextract.c was only intended as a source-code example, not a supported application",
"evidence": "osv:CVE-2018-18586",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2018-18586",
"aliases": [
"CVE-2018-18586"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/kyz/libmspack",
"type": "GIT",
"events": [
{
"introduced": "a22627dd5180e0ce9c558d0c10b174c760085f57"
},
{
"last_affected": "bc1010b120a987de3da053ba61870fcbecfbd112"
},
{
"fixed": "7cadd489698be117c47efcadd742651594429e6d"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:kyzer:libmspack:0.3:alpha:*:*:*:*:*:*",
"range": [
{
"introduced": "0.3-alpha"
},
{
"last_affected": "0.3-alpha"
}
],
"source": "CPE_STRING"
},
{
"cpe": "cpe:2.3:a:kyzer:libmspack:0.4:alpha:*:*:*:*:*:*",
"range": [
{
"introduced": "0.4-alpha"
},
{
"last_affected": "0.4-alpha"
}
],
"source": "CPE_STRING"
},
{
"cpe": "cpe:2.3:a:kyzer:libmspack:0.5:alpha:*:*:*:*:*:*",
"range": [
{
"introduced": "0.5-alpha"
},
{
"last_affected": "0.5-alpha"
}
],
"source": "CPE_STRING"
},
{
"cpe": "cpe:2.3:a:kyzer:libmspack:0.6:alpha:*:*:*:*:*:*",
"range": [
{
"introduced": "0.6-alpha"
},
{
"last_affected": "0.6-alpha"
}
],
"source": "CPE_STRING"
},
{
"cpe": "cpe:2.3:a:kyzer:libmspack:0.7:alpha:*:*:*:*:*:*",
"range": [
{
"introduced": "0.7-alpha"
},
{
"last_affected": "0.7-alpha"
}
],
"source": "CPE_STRING"
},
{
"range": [
{
"fixed": "7cadd489698be117c47efcadd742651594429e6d"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"0.3-alpha",
"0.4-alpha",
"0.5-alpha",
"0.6-alpha",
"0.7-alpha",
"v0.7alpha",
"v0.6alpha",
"v1.5",
"v0.5alpha",
"v0.4alpha",
"v1.4",
"v0.3alpha"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-18586.json",
"vanir_signatures": [
{
"id": "CVE-2018-18586-7505825f",
"digest": {
"threshold": 0.9,
"line_hashes": [
"132217244909678999437045884994041631732",
"118486685220162301588933284659837502589",
"222615661882722935798674702194044547538",
"219466755054797721960266295314213546095",
"121151598458548409255316740935381343568",
"251794852627836227553566778864470334558",
"276386435241628830137813434249006767161",
"175017918290597721448889109973898583339",
"76346329143149834116510719185726473758",
"63418847592787521052761912317172777863",
"178541120143036453390048197284215582459",
"225241872322959364675261907169332432852",
"5687739501093445154981481862495263751",
"215127561223302871173399771134414929721",
"293357833663568891914347203216630066385",
"186174406741438164710290524819104471828",
"293306914388071824781965863647218258380",
"167691164685362533630025839601672666569",
"149824802092469499658294486183158614954",
"254789303695554541346853322408141944304",
"80947747128519016585894919489949934570",
"175320454547622884216682052703172976605",
"120624756470267526030997539398261046599",
"261759257982953005752840463689673345315",
"213928999277667040425900834898570427129",
"70005316954701892465692955578209039965",
"231195700645312976446011945221240415851",
"228196885841981192425952172150817854482",
"174304417751722594597093677375760400835",
"152355533426064100670146862363160293275",
"249762788559237212680438951250333340720",
"87411400792090358020183565937091936690",
"6744364880911807034699269934291871313",
"194583843208136331365198575948792565834",
"9780324754441355153589338133080765820",
"294642448661868398785201737223518408646",
"252457921278666985873737785292667935433",
"158867895338525521147741642841601864584",
"305130856208786088562017513659960910702",
"41904302489867191859186942943233399570",
"174398465214914042445324696526882070075",
"183320402960802003877949183047325896275",
"189508025214272293236424464960845164093",
"101928875653620123931473633201290476150",
"110114845122702344456797587701237160105",
"310776510053239329395433180738797107623",
"8489312533346179172916505379326312764",
"63079483386643476811183316788393478357",
"100537737846989771671509143207413508929",
"242837151747184648146970527131172575458",
"79920160273488118676337121161141022489",
"104268556886586718973627451693583341293",
"284563985493391703476617016659624302384",
"227524432114338156336445170894261347705",
"60636500522078535908579059062906699466",
"41015532848011598996548738304648322688",
"38050941284915674202415563781145260997",
"108765095596990967572773563646003538941",
"198336727089604421929377117405484585559",
"161681440077813729876365982894559509543",
"270424609327362527655435360931025506009",
"135647053476087047233109166941984931369",
"173861429623871299760377822238913944644",
"132669422380041523076200484778224511734",
"1309430708804111996759419706833211170",
"178450306176084823109919980947646734888",
"218810929613725555102614093969984362302",
"2296226440901098574089782012342800808",
"229337352905290427095117294339535507851",
"291655022682040911965606594361371420754",
"98969152067630238017861340398579647254",
"241015714968160062448308658251007238117",
"124076827736943902471002866881412944255",
"53344881501313825978030816336204935628",
"273555304606131816135686695310577248235",
"31175708583529425594189889907309991586",
"191041860770047005057657380764910146537"
]
},
"source": "https://github.com/kyz/libmspack/commit/7cadd489698be117c47efcadd742651594429e6d",
"target": {
"file": "libmspack/src/chmextract.c"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
},
{
"id": "CVE-2018-18586-bb60fb48",
"digest": {
"length": 1269,
"function_hash": "59135860739822885713181976095235092158"
},
"source": "https://github.com/kyz/libmspack/commit/7cadd489698be117c47efcadd742651594429e6d",
"target": {
"file": "libmspack/src/chmextract.c",
"function": "main"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2018-18586-e6dab8e6",
"digest": {
"length": 1807,
"function_hash": "241467629137614069631945326365599028761"
},
"source": "https://github.com/kyz/libmspack/commit/7cadd489698be117c47efcadd742651594429e6d",
"target": {
"file": "libmspack/src/chmextract.c",
"function": "create_output_name"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
}
],
"vanir_signatures_modified": "2026-10-20T13:20:46Z"
}
}
],
"modified": "2026-10-20T13:20:46.327152921Z",
"provider": "osv",
"references": [
"https://bugs.debian.org/911639",
"https://security.gentoo.org/glsa/201903-20",
"https://www.openwall.com/lists/oss-security/2018/10/22/1",
"https://github.com/kyz/libmspack/commit/7cadd489698be117c47efcadd742651594429e6d"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2018-18586",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 387535,
"published_at": "2018-10-23T02:29:00.7+00:00"
}