Multiple vulnerabilities in Sass LibSass

1) Infinite loop

EUVDB-ID: #VU36344

Risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2018-19826

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

** DISPUTED ** In inspect.cpp in LibSass 3.5.5, a high memory footprint caused by an endless loop (containing a Sass::Inspect::operator()(Sass::String_Quoted*) stack frame) may cause a Denial of Service via crafted sass input files with stray '&' or '/' characters. NOTE: Upstream comments indicate this issue is closed as "won't fix" and "works as intended" by design.

Mitigation

Install update from vendor's website.

Vulnerable software versions

LibSass: 3.5.5

CPE2.3

• cpe:2.3:a:sass:libsass:3.5.5:*:*:*:*:*:*:*

External links

https://github.com/sass/libsass/issues/2781

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Use-after-free

EUVDB-ID: #VU36345

Risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2018-19827

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.

In LibSass 3.5.5, a use-after-free vulnerability exists in the SharedPtr class in SharedPtr.cpp (or SharedPtr.hpp) that may cause a denial of service (application crash) or possibly have unspecified other impact.

Mitigation

Install update from vendor's website.

Vulnerable software versions

LibSass: 3.5.5

CPE2.3

• cpe:2.3:a:sass:libsass:3.5.5:*:*:*:*:*:*:*

External links

https://lists.opensuse.org/opensuse-security-announce/2019-07/msg00047.html
https://lists.opensuse.org/opensuse-security-announce/2019-07/msg00051.html
https://lists.opensuse.org/opensuse-security-announce/2019-08/msg00027.html
https://github.com/sass/libsass/issues/2782

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) NULL pointer dereference

EUVDB-ID: #VU36350

Risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2018-19797

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error. A remote attacker can trigger denial of service conditions via a crafted sass input file.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

LibSass: 3.5.5

CPE2.3

• cpe:2.3:a:sass:libsass:3.5.5:*:*:*:*:*:*:*

External links

https://lists.opensuse.org/opensuse-security-announce/2019-07/msg00047.html
https://lists.opensuse.org/opensuse-security-announce/2019-07/msg00051.html
https://lists.opensuse.org/opensuse-security-announce/2019-08/msg00027.html
https://github.com/sass/libsass/issues/2779

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.