First of all, do not panic. Apparently there is a security flaw that was discovered in PGP and GPG that could allow someone to "use the victim’s own email client to decrypt previously acquired messages and return the decrypted content to the attacker without alerting the victim."
Source: https://www.eff.org/deeplinks/2018/05/not-so-pretty-what-you-need-know-about-e-fail-and-pgp-flaw-0
However, its not exactly that.
The flaw has existed for years, and only affects email clients that have not implemented correct mitigations
https://twitter.com/ProtonMail/status/995999392422342656
https://twitter.com/ProtonMail/status/996003952503197697
https://twitter.com/ProtonMail/status/996006094605570048
https://twitter.com/ProtonMail/status/996012067105722368
https://twitter.com/ProtonMail/status/996021514548994053
https://twitter.com/AlecMuffett/status/995941110567571456
In the end, PGP and GPG are safe, as long as you use clients who have properly fixed these flaws
Services like ProtonMail and Enigmail are unaffected
https://twitter.com/ProtonMail/status/995996112526954496
Source: https://www.eff.org/deeplinks/2018/05/not-so-pretty-what-you-need-know-about-e-fail-and-pgp-flaw-0
However, its not exactly that.
The flaw has existed for years, and only affects email clients that have not implemented correct mitigations
https://twitter.com/ProtonMail/status/995999392422342656
https://twitter.com/ProtonMail/status/996003952503197697
https://twitter.com/ProtonMail/status/996006094605570048
https://twitter.com/ProtonMail/status/996012067105722368
https://twitter.com/ProtonMail/status/996021514548994053
https://twitter.com/AlecMuffett/status/995941110567571456
In the end, PGP and GPG are safe, as long as you use clients who have properly fixed these flaws
Services like ProtonMail and Enigmail are unaffected
https://twitter.com/ProtonMail/status/995996112526954496