Your submission was sent successfully! Close

You have successfully unsubscribed! Close

USN-5047-1: Firefox vulnerability

19 August 2021

Firefox could be made to incorrectly accept newlines in HTTP/3 response headers.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Releases

Packages

  • firefox - Mozilla Open Source web browser

Details

It was discovered that Firefox could be made to incorrectly accept
newlines in HTTP/3 response headers. If a user were tricked into
opening a specially crafted website, an attacker could exploit this
to conduct header splitting attacks.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 21.04
Ubuntu 20.04
Ubuntu 18.04

After a standard system update you need to restart Firefox to make
all the necessary changes.

References

Related notices

  • USN-5248-1: thunderbird-locale-ms, thunderbird-locale-lt, thunderbird-locale-sv, thunderbird-locale-be, thunderbird-locale-dsb, thunderbird-locale-gl, thunderbird-locale-ta-lk, thunderbird-locale-it, thunderbird-locale-zh-hans, xul-ext-lightning, thunderbird-locale-ta, thunderbird-locale-ro, thunderbird-locale-vi, thunderbird-locale-sk, thunderbird-locale-cak, thunderbird-locale-bg, thunderbird-locale-fy, xul-ext-calendar-timezones, thunderbird-locale-es-ar, thunderbird-locale-pt-br, thunderbird-locale-en-gb, thunderbird-locale-fi, thunderbird-locale-es, thunderbird-locale-uz, thunderbird, thunderbird-locale-bn, thunderbird-locale-fr, thunderbird-locale-nl, thunderbird-locale-pl, thunderbird-locale-zh-cn, thunderbird-locale-hu, thunderbird-locale-si, thunderbird-locale-sv-se, thunderbird-locale-kab, thunderbird-dev, thunderbird-locale-nb, thunderbird-locale-ar, thunderbird-locale-lv, thunderbird-locale-fy-nl, thunderbird-locale-ca, thunderbird-locale-en, thunderbird-locale-kk, thunderbird-locale-br, thunderbird-locale-cy, thunderbird-locale-et, thunderbird-locale-gd, thunderbird-locale-ja, thunderbird-locale-hr, thunderbird-locale-ga, thunderbird-locale-ast, thunderbird-locale-pt, thunderbird-locale-is, thunderbird-locale-ka, thunderbird-locale-cs, thunderbird-locale-tr, thunderbird-locale-nn-no, thunderbird-locale-hy, thunderbird-locale-pa-in, thunderbird-locale-sq, thunderbird-mozsymbols, thunderbird-locale-nn, thunderbird-locale-ru, thunderbird-locale-es-es, thunderbird-locale-th, thunderbird-locale-sl, thunderbird-locale-id, thunderbird-gnome-support, thunderbird-locale-rm, thunderbird-locale-uk, thunderbird-locale-pa, thunderbird-locale-zh-tw, thunderbird-locale-el, thunderbird-locale-ga-ie, thunderbird-locale-he, thunderbird-locale-eu, thunderbird-locale-bn-bd, thunderbird-locale-af, thunderbird-locale-da, thunderbird-locale-nb-no, xul-ext-gdata-provider, thunderbird-locale-zh-hant, thunderbird-locale-de, thunderbird-locale-en-us, thunderbird-locale-pt-pt, thunderbird-locale-hsb, thunderbird-locale-mk, thunderbird-locale-ko, thunderbird-locale-fa, thunderbird-locale-sr