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CVE-2026-19499

CVE-2026-19499 · Buffer overflow in strfmon and strfmon_l right-justification padding

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Calling strfmon and strfmon_l in the GNU C Library version 2.38 to 2.44 can write past the end of the caller-supplied output buffer when a conversion uses right-justified width padding. Exploitation requires an application code path that calls strfmon or strfmon_l with right-justified width padding into a destination buffer that is large enough for the padding to succeed but too small for the internal memmove call. The field width or format may be attacker-influenced or a fixed susceptible pattern in the caller. At the time of publication, no network-facing application impact is known.

CVSS 7.7 · High · EPSS 0.3% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • glibc

    Versions
    • ≥ 2.38, ≤ 2.44: Affected (custom)

    No fix published

  • glibc Debian:12

    Versions
    • 2.36-10~0
    • 2.36-9
    • 2.36-9+deb12u1
    • 2.36-9+deb12u10
    • 2.36-9+deb12u11
    • 2.36-9+deb12u12
    • 2.36-9+deb12u13
    • 2.36-9+deb12u14
    • 2.36-9+deb12u2
    • 2.36-9+deb12u3
    • 2.36-9+deb12u4
    • 2.36-9+deb12u5
    • 2.36-9+deb12u6
    • 2.36-9+deb12u7
    • 2.36-9+deb12u8
    • 2.36-9+deb12u9
    • 2.36-9+loong64
    • 2.37-1
    • 2.37-10
    • 2.37-11
    • 2.37-12
    • 2.37-13
    • 2.37-14
    • 2.37-15
    • 2.37-15.1
    • 2.37-15.1+sh4
    • 2.37-15~deb13u1
    • 2.37-16
    • 2.37-17
    • 2.37-18
    • 2.37-19
    • 2.37-2
    • 2.37-3
    • 2.37-4
    • 2.37-5
    • 2.37-6
    • 2.37-7
    • 2.37-8
    • 2.37-9
    • 2.38-1
    • 2.38-10
    • 2.38-11
    • 2.38-12
    • 2.38-12.1
    • 2.38-13
    • 2.38-14
    • 2.38-15~0
    • 2.38-15~1
    • 2.38-2
    • 2.38-3
    • 2.38-4
    • 2.38-5
    • 2.38-6
    • 2.38-7
    • 2.38-7~0+hurd.1
    • 2.38-8
    • 2.38-9
    • 2.39-1
    • 2.39-2
    • 2.39-3
    • 2.39-3.1
    • 2.39-4
    • 2.39-5
    • 2.39-6
    • 2.39-6+hurd.1
    • 2.39-6+sh4
    • 2.39-7
    • 2.39-7+sh4
    • 2.39-7~0
    • 2.39-8~0
    • 2.40-1
    • 2.40-2
    • 2.40-2+sh4
    • 2.40-3
    • 2.40-3+sh4
    • 2.40-4
    • 2.40-5
    • 2.40-5~hurd.1
    • 2.40-6
    • 2.40-6~1
    • 2.40-7
    • 2.41-1
    • 2.41-10
    • 2.41-11
    • 2.41-12
    • 2.41-13~hurd.0
    • 2.41-13~hurd.1
    • 2.41-2
    • 2.41-3
    • 2.41-4
    • 2.41-4~0
    • 2.41-5
    • 2.41-5~0
    • 2.41-6
    • 2.41-7
    • 2.41-8
    • 2.41-8~0
    • 2.41-8~1
    • 2.41-9
    • 2.41-9~0
    • 2.41-9~1
    • 2.42-1
    • 2.42-10
    • 2.42-11
    • 2.42-12
    • 2.42-12~hurd.1
    • 2.42-13
    • 2.42-14
    • 2.42-14~hurd.1
    • 2.42-15
    • 2.42-15~hurd.1
    • 2.42-16
    • 2.42-17
    • 2.42-2
    • 2.42-3
    • 2.42-4
    • 2.42-5
    • 2.42-6
    • 2.42-7
    • 2.42-8
    • 2.42-8~hurd.1
    • 2.42-8~hurd.2
    • 2.42-9
    • 2.43-1
    • 2.43-2
    • 2.43-3
    • 2.43-3+m68k
    • 2.43-4
    • 2.43-4+m68k
    • 2.43-5
    • 2.43-6
    • 2.43-7~hurd.1
    • 2.44-1
    • 2.44-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • glibc Debian:13

    Versions
    • 2.41-12
    • 2.41-12+deb13u1
    • 2.41-12+deb13u2
    • 2.41-12+deb13u3
    • 2.41-12+deb13u4
    • 2.41-13~hurd.0
    • 2.41-13~hurd.1
    • 2.42-1
    • 2.42-10
    • 2.42-11
    • 2.42-12
    • 2.42-12~hurd.1
    • 2.42-13
    • 2.42-14
    • 2.42-14~hurd.1
    • 2.42-15
    • 2.42-15~hurd.1
    • 2.42-16
    • 2.42-17
    • 2.42-2
    • 2.42-3
    • 2.42-4
    • 2.42-5
    • 2.42-6
    • 2.42-7
    • 2.42-8
    • 2.42-8~hurd.1
    • 2.42-8~hurd.2
    • 2.42-9
    • 2.43-1
    • 2.43-2
    • 2.43-3
    • 2.43-3+m68k
    • 2.43-4
    • 2.43-4+m68k
    • 2.43-5
    • 2.43-6
    • 2.43-7~hurd.1
    • 2.44-1
    • 2.44-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • glibc Debian:14

    Versions
    • 2.41-12
    • 2.41-13~hurd.0
    • 2.41-13~hurd.1
    • 2.42-1
    • 2.42-10
    • 2.42-11
    • 2.42-12
    • 2.42-12~hurd.1
    • 2.42-13
    • 2.42-14
    • 2.42-14~hurd.1
    • 2.42-15
    • 2.42-15~hurd.1
    • 2.42-16
    • 2.42-17
    • 2.42-2
    • 2.42-3
    • 2.42-4
    • 2.42-5
    • 2.42-6
    • 2.42-7
    • 2.42-8
    • 2.42-8~hurd.1
    • 2.42-8~hurd.2
    • 2.42-9
    • 2.43-1
    • 2.43-2
    • 2.43-3
    • 2.43-3+m68k
    • 2.43-4
    • 2.43-4+m68k
    Affected ranges
    • ECOSYSTEM: < 2.43-5

    Update to 2.43-5

  • glibc Ubuntu:24.04:LTS

    Versions
    • 2.38-1ubuntu6
    • 2.38-3ubuntu1
    • 2.39-0ubuntu1
    • 2.39-0ubuntu2
    • 2.39-0ubuntu6
    • 2.39-0ubuntu8
    • 2.39-0ubuntu8.1
    • 2.39-0ubuntu8.2
    • 2.39-0ubuntu8.3
    • 2.39-0ubuntu8.4
    • 2.39-0ubuntu8.5
    • 2.39-0ubuntu8.6
    • 2.39-0ubuntu8.7
    • 2.39-0ubuntu8.8
    Affected ranges
    • ECOSYSTEM: < 2.39-0ubuntu8.9

    Update to 2.39-0ubuntu8.9

  • glibc Ubuntu:26.04:LTS

    Versions
    • 2.42-0ubuntu3
    • 2.42-2ubuntu1
    • 2.42-2ubuntu2
    • 2.42-2ubuntu4
    • 2.42-2ubuntu5
    • 2.43-2ubuntu1
    • 2.43-2ubuntu2
    • 2.43-2ubuntu2.3
    Affected ranges
    • ECOSYSTEM: < 2.43-2ubuntu2.4

    Update to 2.43-2ubuntu2.4

Original sources

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