Answer in brief
CVE-2026-23472 records a Unknown severity vulnerability in serial: core: fix infinite loop in handle_tx() for PORT_UNKNOWN. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c9e845014723d552944cec4e146ec7b841cda34d || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d45cfa70bf0159afb31cb03d2d16ec5a5053460c || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <efe85a557186b7fe915572ae93a8f3f78bfd9a22 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <bc70f2b36cf474d5cc8ecbcaf57f3e326fdec67c || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <455ce986fa356ff43a43c0d363ba95fa152f21d5 | c9e845014723d552944cec4e146ec7b841cda34d, d45cfa70bf0159afb31cb03d2d16ec5a5053460c, efe85a557186b7fe915572ae93a8f3f78bfd9a22, bc70f2b36cf474d5cc8ecbcaf57f3e326fdec67c, 455ce986fa356ff43a43c0d363ba95fa152f21d5 |
| Linux/Linuxgeneric | 2.6.12 | Not reported |
Published upstream
Apr 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 21, 2026
In the Linux kernel, the following vulnerability has been resolved: serial: core: fix infinite loop in handle_tx() for PORT_UNKNOWN uart_write_room() and uart_write() behave inconsistently when xmit_buf is NULL (which happens for PORT_UNKNOWN ports that were never properly initialized): - uart_write_room() returns kfifo_avail() which can be > 0 - uart_write() checks xmit_buf and returns 0 if NULL This inconsistency causes an infinite loop in drivers that rely on tty_write_room() to determine if they can write: while (tty_write_room(tty) > 0) { written = tty->ops->write(...); // written is always 0, loop never exits } For example, caif_serial's handle_tx() enters an infinite loop when used with PORT_UNKNOWN serial ports, causing system hangs. Fix by making uart_write_room() also check xmit_buf and return 0 if it's NULL, consistent with uart_write(). Reproducer: https://gist.github.com/mrpre/d9a694cc0e19828ee3bc3b37983fde13
Quoted source text, attributed separately from HOL analysis.