Description
In LibSass prior to 3.5.5, Sass::Eval::operator()(Sass::Binary_Expression*) inside eval.cpp allows attackers to cause a denial-of-service resulting from stack consumption via a crafted sass file, because of certain incorrect parsing of '%' as a modulo operator in parser.cpp.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libsass | 3.5.4+20180621~c0a6cf3-1 | — |
| Debian 13 | libsass | 3.5.4+20180621~c0a6cf3-1 | — |
| Debian 12 | libsass | 3.5.4+20180621~c0a6cf3-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | libsass | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | libsass | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SUSE Package Hub 15 SP1 | libsass | 3.6.1-bp151.4.3.1 | openSUSE-SU-2019:1883-1 |
| SUSE Package Hub 15 | libsass | 3.6.1-bp150.3.3.1 | openSUSE-SU-2019:1800-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.1 | libsass | 3.6.1-lp151.3.3.1 | openSUSE-SU-2019:1791-1 |
| openSUSE Leap 15.0 | libsass | 3.6.1-lp151.3.3.1 | openSUSE-SU-2019:1791-1 |
Advisories 3
- openSUSE-SU-2019:1800-1 Security update for libsass SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:1883-1 Security update for libsass SUSE / openSUSE Security Updates · May 7, 2025
- openSUSE-SU-2019:1791-1 Security update for libsass SUSE / openSUSE Security Updates · May 7, 2025
References
- https://github.com/sass/libsass/issues/2659
- https://github.com/sass/libsass/commit/210fdff7a65370c2ae24e022a2b35da8c423cc5f
- openSUSE-SU-2019:1791 vendor-advisory
- openSUSE-SU-2019:1800 vendor-advisory
- openSUSE-SU-2019:1883 vendor-advisory