MediumFix available
undertow — security advisory
An information leak vulnerability was found in Undertow. If all headers are not written out in the first write() call then the code that handles flushing the buffer will always write out the full contents of the writevBuffer buffer, which may contain data from previous requests.
- Products
- undertow
- Affected versions
- 1.3.11-1, 1.3.16-1, 1.3.16-1ubuntu0.1~esm1, 1.3.4-1, 1.3.5-1, 1.3.7-1, 1.4.20-1, 1.4.21-1, 1.4.22-1, 1.4.23-1, 1.4.23-2build1, 1.4.23-3, 1.4.23-3ubuntu0.1~esm1, 2.3.18-1, 2.3.18-2, 2.3.20-1, 2.3.20-1ubuntu1, 2.3.8-2, 2.3.8-2ubuntu0.1~esm1
- Fixed versions
- 2.0.23-1
- CVEs
- CVE-2018-14642
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 00:26 UTC · Revision 1
Source evidence
An information leak vulnerability was found in Undertow. If all headers are not written out in the first write() call then the code that handles flushing the buffer will always write out the full contents of the writevBuffer buffer, which may contain data from previous requests.
osv:UBUNTU-CVE-2018-14642
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
undertow
Fixed versions: 2.0.23-1
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
Complete source record
{
"id": "94733b108476fec3d1973ddc4399474b7fd7b6859de6bbb9db38f4a45e89eed6",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2018-14642",
"method": "structured",
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"modified": "2026-10-17T12:54:55.122952047Z",
"provider": "osv",
"upstream": [
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],
"references": [
"https://ubuntu.com/security/CVE-2018-14642",
"https://bugzilla.redhat.com/show_bug.cgi?id=1628702",
"https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-14642",
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"source_id": "core-osv",
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"published_at": "2018-09-18T13:29:00+00:00"
}