libxml2-2.15.4

[Bruce Dubbs]

New point version.

[Joe Locash]

v2.15.4: Sep 01 2026

### Security

- xmlregexp: Prevent out-of-bounds read in NXT macro
- fix: add missing overflow checks in dict.c, uri.c, and valid.c
- xmlregexp: Calc string length after null checking
- xpointer: Check overflow in xmlXPtrEvalXPtrPart
- xmlIO: Check for int overflow before calling writecallback
- fix(xinclude): propagate parseFlags in xmlXIncludeProcess and xmlXIncludeProcessTree

### Improvements

- Improve bound checks for xmlcatalog and xmllint arguments (out-of-bound)
- Fix memory leak in static Windows library (memory-leak)
- xmlreader: Copy DTD in xmlTextReaderDumpCopy
- parser: Fix double free in xmlIOParseDTD (double-free)
- parser: fix division-by-zero when maxAmpl is set to 0
- parser: Fix memory leak in xmlCtxtSetSaxHandler (memory-leak)
- catalog: Make sure to reset catalog resolve cache
- xmlAddChild: unlink node before free for text nodes (memory-leak)
- Normalize entity values in attr in xmlNodeGetContent
- Handle whitespace for date/time/duration types
- catalog: Fix NULL deref for nextCatalog without 'catalog' attribute (null-deref)

The issues have been assigned these CVE's so far: CVE-2026-86137, CVE-2026-86138, CVE-2026-86139, CVE-2026-86140, CVE-2026-86141, CVE-2026-86142, CVE-2026-86143, CVE-2026-86144

[Joe Locash]

Fixed at 3eff75f36a. Leaving open for SA.

[Bruce Dubbs]

Advisory sa-13.1-013 has been issued.