Critical
Security advisory
An issue was discovered in WeeChat before 2.7.1 (0.3.4 to 2.7 are affected). When a new IRC message 005 is received with longer nick prefixes, a buffer overflow and possibly a crash can happen when a new mode is set for a nick.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2020-9760
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:42 UTC · Revision 1
Source evidence
An issue was discovered in WeeChat before 2.7.1 (0.3.4 to 2.7 are affected). When a new IRC message 005 is received with longer nick prefixes, a buffer overflow and possibly a crash can happen when a new mode is set for a nick.
osv:CVE-2020-9760
Complete source record
{
"id": "94a6dc50e0c1f7e564b08c9f3f53039d01eed4997139178fbd7e646b6f22caf5",
"url": "https://osv.dev/vulnerability/CVE-2020-9760",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2020-9760",
"summary": "An issue was discovered in WeeChat before 2.7.1 (0.3.4 to 2.7 are affected). When a new IRC message 005 is received with longer nick prefixes, a buffer overflow and possibly a crash can happen when a new mode is set for a nick.",
"evidence": "osv:CVE-2020-9760",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2020-9760",
"aliases": [
"CVE-2020-9760"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/weechat/weechat",
"type": "GIT",
"events": [
{
"introduced": "0b89084ea4dc5cfe353541a41059d62b62d8dc84"
},
{
"fixed": "5c0aa1aae7ac3e209acf62cce6eacffcc887cc98"
},
{
"fixed": "40ccacb4330a64802b1f1e28ed9a6b6d3ca9197f"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:weechat:weechat:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0.3.4"
},
{
"fixed": "2.7.1"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "40ccacb4330a64802b1f1e28ed9a6b6d3ca9197f"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"v2.3",
"v2.7",
"v2.7-rc1",
"v2.6",
"v2.6-rc2",
"v2.6-rc1",
"v2.5",
"v2.5-rc2",
"v2.5-rc1",
"v2.4",
"v2.4-rc1",
"v2.3-rc1",
"v2.2",
"v2.2-rc2",
"v2.2-rc1",
"v2.1",
"v2.1-rc1",
"v2.0",
"v2.0-rc1",
"v1.9",
"v1.9-rc2",
"v1.9-rc1",
"v1.8",
"v1.8-rc1",
"v1.7",
"v1.7-rc2",
"v1.7-rc1",
"v1.6",
"v1.6-rc2",
"v1.6-rc1",
"v1.5",
"v1.5-rc2",
"v1.5-rc1",
"v1.4",
"v1.4-rc2",
"v1.4-rc1",
"v1.3",
"v1.3-rc2",
"v1.3-rc1",
"v1.2",
"v1.2-rc2",
"v1.2-rc1",
"v1.1",
"v1.1-rc2",
"v1.1-rc1",
"v1.0",
"v1.0-rc3",
"v1.0-rc2",
"v1.0-rc1",
"v0.4.3",
"v0.4.3-rc2",
"v0.4.3-rc1",
"v0.4.2",
"v0.4.2-rc2",
"v0.4.2-rc1",
"v0.4.1",
"v0.4.1-rc2",
"v0.4.1-rc1",
"v0.4.0",
"v0.4.0-rc3",
"v0.4.0-rc2",
"v0.4.0-rc1",
"v0.3.9",
"v0.3.9-rc2",
"v0.3.9-rc1",
"v0.3.8",
"v0.3.8-rc2",
"v0.3.8-rc1",
"v0.3.7",
"v0.3.7-rc3",
"v0.3.7-rc2",
"v0.3.7-rc1",
"v0.3.6",
"v0.3.6-rc3",
"v0.3.6-rc2",
"v0.3.6-rc1",
"v0.3.5",
"v0.3.5-rc3",
"v0.3.5-rc2",
"v0.3.5-rc1",
"v0.3.4"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-9760.json",
"vanir_signatures": [
{
"id": "CVE-2020-9760-24b17d3c",
"digest": {
"threshold": 0.9,
"line_hashes": [
"325596194213706182479652272081936598340",
"132268216224256037571839750429924175280",
"44497950053967307772718137244273875544",
"132550677232131315184311444001429665351",
"97418110254259639727718916227023582353",
"149303952922933676077113852457245993771",
"129402597196439469058390957584289549233",
"108587633537507210242609878158511307392",
"111708766549982062342636204382193101079",
"167118086744474657822052685044811994853"
]
},
"source": "https://github.com/weechat/weechat/commit/40ccacb4330a64802b1f1e28ed9a6b6d3ca9197f",
"target": {
"file": "src/plugins/irc/irc-server.c"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
},
{
"id": "CVE-2020-9760-6054fd6a",
"digest": {
"threshold": 0.9,
"line_hashes": [
"213054129778902522372905892267968144680",
"131097610739893464754850419081481526954",
"228471673978473928265094791230654823703",
"197161856197992666943380620234508962100"
]
},
"source": "https://github.com/weechat/weechat/commit/40ccacb4330a64802b1f1e28ed9a6b6d3ca9197f",
"target": {
"file": "src/plugins/irc/irc-nick.h"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
},
{
"id": "CVE-2020-9760-a185fca6",
"digest": {
"length": 863,
"function_hash": "128916233876534572922588486440859965445"
},
"source": "https://github.com/weechat/weechat/commit/40ccacb4330a64802b1f1e28ed9a6b6d3ca9197f",
"target": {
"file": "src/plugins/irc/irc-server.c",
"function": "irc_server_set_prefix_modes_chars"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
}
],
"vanir_signatures_modified": "2026-10-20T14:15:08Z"
}
}
],
"modified": "2026-10-20T14:15:08.387063450Z",
"provider": "osv",
"references": [
"https://lists.debian.org/debian-lts-announce/2020/03/msg00031.html",
"https://lists.debian.org/debian-lts-announce/2021/09/msg00018.html",
"https://security.gentoo.org/glsa/202003-51",
"https://weechat.org/doc/security/",
"https://github.com/weechat/weechat/commit/40ccacb4330a64802b1f1e28ed9a6b6d3ca9197f"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*",
"cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"
],
"vendor_product": "debian:debian_linux",
"extracted_events": [
{
"range": [
{
"introduced": "8.0"
},
{
"last_affected": "8.0"
},
{
"introduced": "9.0"
},
{
"last_affected": "9.0"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2020-9760",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 388766,
"published_at": "2020-03-23T16:15:17.923+00:00"
}