YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via an unbounded newline scan in newline_len
YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via an unbounded newline scan in newline_len. In the bundled libsyck newline_len and is_newline dereference the scan pointer, and the following byte for a "\r\n" pair, with no NUL-terminator or bounds check. During block-scalar lexing at a document boundary the scan runs one byte past the heap lexer buffer. This is an incomplete fix of CVE-2025-11683, on a lexer path the earlier fix did not cover. Any caller that runs Load or LoadFile on an untrusted document with a block scalar at a document boundary reaches the over-read.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-57077
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 8 Nov 2026, 03:48 UTC · Revision 1
Source evidence
YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via an unbounded newline scan in newline_len
core-osv · Original sourcePublished 16 Jul 2026, 21:41 UTC
YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via an unbounded newline scan in newline_len. In the bundled libsyck newline_len and is_newline dereference the scan pointer, and the following byte for a "\r\n" pair, with no NUL-terminator or bounds check. During block-scalar lexing at a document boundary the scan runs one byte past the heap lexer buffer. This is an incomplete fix of CVE-2025-11683, on a lexer path the earlier fix did not cover. Any caller that runs Load or LoadFile on an untrusted document with a block scalar at a document boundary reaches the over-read.
osv:CVE-2026-57077
Complete source record
{
"id": "657570ddc6fce5b6d62e95ed6ddcc55a2caad2950161f83120379921f2e361d8",
"url": "https://osv.dev/vulnerability/CVE-2026-57077",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via an unbounded newline scan in newline_len",
"summary": "YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via an unbounded newline scan in newline_len. In the bundled libsyck newline_len and is_newline dereference the scan pointer, and the following byte for a \"\\r\\n\" pair, with no NUL-terminator or bounds check. During block-scalar lexing at a document boundary the scan runs one byte past the heap lexer buffer. This is an incomplete fix of CVE-2025-11683, on a lexer path the earlier fix did not cover. Any caller that runs Load or LoadFile on an untrusted document with a block scalar at a document boundary reaches the over-read.",
"evidence": "osv:CVE-2026-57077",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-57077",
"aliases": [
"CVE-2026-57077"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/cpan-authors/YAML-Syck",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "d7f942870d2f57b17dd5db1b3714eff448c34cd6"
}
],
"database_specific": {
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "1.47"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
},
{
"range": [
{
"fixed": "44c90a109ec3215ee7ce747bd11209835e123d8b"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
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"1.45",
"1.44",
"1.43",
"1.42",
"1.41",
"1.39",
"1.38",
"1.37",
"1.37_01",
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"0.91",
"0.90",
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"0.81",
"0.80",
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"0.66",
"0.65",
"0.64",
"0.63",
"0.62",
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"0.60",
"0.46_01",
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"0.34",
"0.33",
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"0.31",
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"0.22",
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"0.18",
"0.17",
"0.16",
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"0.14",
"0.13",
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"0.11",
"0.10",
"0.09",
"0.08",
"0.07",
"0.06",
"0.05",
"0.04",
"0.03",
"0.02",
"0.01"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-57077.json"
}
}
],
"modified": "2026-10-28T02:30:53.350677181Z",
"provider": "osv",
"references": [
"https://cpan.org/modules",
"https://www.cve.org/CVERecord?id=CVE-2025-11683",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57077.json",
"https://metacpan.org/release/TODDR/YAML-Syck-1.47/changes",
"https://nvd.nist.gov/vuln/detail/CVE-2026-57077",
"https://github.com/toddr/YAML-Syck/commit/44c90a109ec3215ee7ce747bd11209835e123d8b.patch",
"https://github.com/toddr/YAML-Syck"
],
"provider_metadata": {
"cwe_ids": [
"CWE-125"
],
"cna_assigner": "CPANSec",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57077.json"
}
},
"related_cves": [
{
"value": "CVE-2026-57077",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 522342,
"published_at": "2026-07-16T21:41:52.038+00:00"
}