zlib: Buffer Overflow in Zlib::GzipReader ungetc via large input leads to memory corruption

• azl3 ruby 3.3.5-8 on Azure Linux 3.0

• azl3 zlib 1.3.2-1 on Azure Linux 3.0

• azl3 ruby 3.3.5-7 on Azure Linux 3.0

SecurityAlert records field-level changes from the point we begin following a bulletin. Earlier vendor changes may not have a field-by-field record.

1. Oct 8, 2026 at 9:05 AM UTC
   • Added affected products: azl3 ruby 3.3.5-8 on Azure Linux 3.0.

1. Apr 18, 2026 at 1:01 AM UTC
   Published by Microsoft Security Response Center

   The publication date reported by the vendor.

2. May 6, 2026 at 2:52 PM UTC
   Updated by Microsoft Security Response Center

   The vendor changed the advisory after it was first published.

3. Sep 27, 2026 at 11:11 PM UTC
   Added to SecurityAlert

   We collected the advisory from the official source.

4. Nov 1, 2026 at 11:20 PM UTC
   Confirmed at the source

   Our collector saw this advisory during a later source check.