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.
Analysis and contextual insights are available on OpenCVE Cloud.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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| Source | ID | Title |
|---|---|---|
Ubuntu USN |
USN-8737-1 | GNU C Library vulnerabilities |
Ubuntu USN |
USN-8737-2 | GNU C Library vulnerabilities |
Mon, 14 Sep 2026 21:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | A flaw was found in glibc. The strfmon and strfmon_l functions are vulnerable to a buffer overflow when processing right-justified width padding. This occurs because an incorrect length is used for an internal memory operation, causing data to be written beyond its intended buffer. An attacker could exploit this by providing specially crafted input, potentially leading to arbitrary code execution or other severe impacts. | 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. |
| Title | glibc: Buffer Overflow in strfmon right-justification padding | Buffer overflow in strfmon and strfmon_l right-justification padding |
| Weaknesses | CWE-122 | |
| References |
| |
| Metrics |
cvssV3_1
|
ssvc
|
Mon, 31 Aug 2026 21:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Gnu
Gnu glibc |
|
| Vendors & Products |
Gnu
Gnu glibc |
Tue, 25 Aug 2026 12:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | A flaw was found in glibc. The strfmon and strfmon_l functions are vulnerable to a buffer overflow when processing right-justified width padding. This occurs because an incorrect length is used for an internal memory operation, causing data to be written beyond its intended buffer. An attacker could exploit this by providing specially crafted input, potentially leading to arbitrary code execution or other severe impacts. | |
| Title | glibc: Buffer Overflow in strfmon right-justification padding | |
| Weaknesses | CWE-787 | |
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Status: PUBLISHED
Assigner: glibc
Published:
Updated: 2026-09-14T19:40:43.330Z
Reserved: 2026-08-10T18:42:03.154Z
Link: CVE-2026-19499
Updated: 2026-09-14T19:40:39.869Z
Status : Received
Published: 2026-09-14T18:17:45.753
Modified: 2026-09-14T20:16:43.250
Link: CVE-2026-19499
OpenCVE Enrichment
Updated: 2026-09-15T13:45:07Z
Ubuntu USN