Out-of-bounds write via stale post-padding length
Published Sep 14, 2026 · Updated Sep 14, 2026
Out-of-bounds write in GNU C Library 2.38 through 2.44 allows local users to corrupt process memory via monetary-format padding. In strfmon_l, __printf_buffer_pad advances the buffer pointers, but a later memmove uses the stale pre-padding length and writes past the caller-supplied buffer. Reachability requires an application to invoke strfmon or strfmon_l with right-justified padding and a destination that fits the padding but not the overlong move; no network-facing application impact is known.
Summary
What happened
Out-of-bounds write in GNU C Library 2.38 through 2.44 allows local users to corrupt process memory via monetary-format padding. In strfmon_l, __printf_buffer_pad advances the buffer pointers, but a later memmove uses the stale pre-padding length and writes past the caller-supplied buffer. Reachability requires an application to invoke strfmon or strfmon_l with right-justified padding and a destination that fits the padding but not the overlong move; no network-facing application impact is known.
The record
- CVE
- CVE-2026-19499
- Published
- Sep 14, 2026
- Updated
- Sep 14, 2026
- Vendor
- The GnuPG Project
- Product
- glibc
- Classifications
- CWE-787
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 14, 2026CVE publishedPublication date reported by the CVE source.
- Sep 14, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=2.38 <=2.44
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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