#VU81132 Out-of-bounds write in Mozilla Firefox and Firefox for Android - CVE-2023-5173

Vulnerability identifier: #VU81132

Vulnerability risk: Medium

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-5173

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mozilla Firefox
Client/Desktop applications / Web browsers
Firefox for Android
Mobile applications / Apps for mobile phones

Vendor: Mozilla

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input. A remote attacker can trick the victim to open a specially crafted HTML file to trigger an out-of-bounds write and execute arbitrary code on the target system.

The vulnerability affects Firefox if a non-standard preference allowing non-HTTPS Alternate Services (network.http.altsvc.oe) is enabled.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 116.0 - 117.0.1

Firefox for Android: 116.0 - 117.1.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2023-41/

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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.