Ubuntu 25.10 : libxml2.so.2: cannot open shared object file

[pol2095]

Problem Description

• AIR SDK 51.2.2.6
• Ubuntu 25.10

Steps to Reproduce

when I launch an Air app on Ubuntu 25.10, I have this message error :

Error loading the runtime (libxml2.so.2: cannot open shared object file: No such file or directory)

Known Workarounds

no workaround, it's impossible to install libxml2 using apt

I tried :

sudo ln -s /usr/lib/x86_64-linux-gnu/libxml2.so.16 /usr/lib/x86_64-linux-gnu/libxml2.so.2

I have this message error :

Error loading the runtime (/home/user/myAPP/Adobe AIR/Versions/1.0/libCore.so: undefined symbol: xmlLoadExtDtdDefaultValue, version LIBXML2_2.4.30)

[AdamHarte]

Do we know when this started happening? Did the previous version of AIR SDK work?

[pol2095]

Ubuntu has been updated libxml2.so.2 to libxml2.so.16 and no version of Air work on the lastest Ubuntu...

[AdamHarte]

Do we know if it was Ubuntu 25.10 specifically that updated the library? I am wondering how far back I need to go to have it running

[pol2095]

It would be good to have a response from Harman.

[ajwfrost]

Sorry for the delay @pol2095, we've not yet had a chance to look into this properly yet but I would expect there are a couple of options. If your initial workaround failed then that basically means there's a binary incompatibility in their update, which is always frustrating. Trying to support older operating system versions as well as new ones is quite tricky on some platforms (it's one thing that I think Microsoft actually have got right..)

Anyway: options we have:

1. Distribute our build of the libxml2 library within the 'Resources' folder in AIR. Which I actually think we do (or did) for some libraries?
2. Look at switching to a dynamic loading and symbol resolution mechanism which would allow it to pick up different platform versions - which is probably the best/most complete option.
3. Rebuild against a more recent version of the library and therefore drop support for older Linux versions. Which is possibly the easiest route for us, but probably not one that would be appreciated more generally :-)

Let me check with the team on the effort for option 2, in the meantime it might actually work to copy the older version of the library (if you can get hold of it) into the Resources folder since I think the libCore.so library already has that in the rpath setting..

thanks

[pol2095]

I tried to add libxml2.so.2 in Resources folder, but libxml2 need two dependencies libicuuc.so.74 (now libicuuc.so.76 in ubuntu 25.10) and libicudata.so.74 (now libicudata.so.76 in ubuntu 25.10) and Adobe Air work.