Will avast detect apps modified to take advantage of the just announced cryptographic signature exploit?

See the following for more info.

http://bluebox.com/corporate-blog/bluebox-uncovers-android-master-key/

http://bluebox.com/corporate-blog/free-scanner-to-manage-risk-of-major-android-vulnerability/

http://arstechnica.com/security/2013/07/google-patches-critical-android-threat-as-working-exploit-is-unleashed/

https://jira.cyanogenmod.org/browse/CYAN-1602

http://review.cyanogenmod.org/#/c/45251/

https://gist.github.com/poliva/36b0795ab79ad6f14fd8

http://www.digitaltrends.com/mobile/android-bluebox-virus-exploit-not-that-bad/

http://arstechnica.com/security/2013/07/android-flaw-allows-hackers-to-surreptitiously-modify-apps/

http://www.theverge.com/2013/7/3/4491862/four-year-old-android-bug-affects-99-percent-of-devices

http://www.maximumpc.com/security_firm_finds_gaping_hole_android’s_security_fabric200

Scan your device for that here: http://bluebox.com/?p=721 (article author = Jeff Forristal)
Bluebox Security Scanner → https://play.google.com/store/apps/details?id=com.bluebox.labs.onerootscanner

polonus

Yes. (See screenshot: http://forum.avast.com/index.php?msg=964992)